To title page of Tertiary Marine Pelecypods of California and Baja California

[Please cite as follows: Moore, E.J., 2003, Family Tellinidae, in Tertiary marine pelecypods of California and Baja California, Chapter G: http://www.cmug.com/~chintimp/Tellinidae.htm, 55 p., 7 pl.]

Family TELLINIDAE

“Shell aragonitic, with prismatic outer, crossed-lamellar middle, and complex crossed-lamellar inner layers. Usually with rounded anterior end and elongate posterior end, equivalve to inequivalve, occasionally with posterior flexure. Sculpture variable, commarinal and subdued***Hinge plate narrow; two cardinal teeth in each valve; lateral teeth, when present, stronger in right valve***Pallial line strong; pallial sinus deep, frequently differing in the two valves.

“The family is known from the Cretaceous and consists of active infaunal dwellers of mud and sand. Most have been secondarily modified as deposit feeders, using the long inhalant siphon to sweep the superficial detritus layer.” (Coan, Scott, and Bernard, 2000, p. 398)

Genus TELLINA Linné, 1758

“Shell elongate, compressed. Hinge plate with two cardinal teeth in each valve and lateral teeth in one or both valves, sometimes overgrown in adults.***Tellina, s.s., ***does not occur in the northeastern Pacific.***” (Coan, Scott, and Bernard, 2000, p. 398)

Subgenus ANGULUS von Muhlfeld, 1811

“Shell elongate, compressed, thin. Posterior end broadly truncate. Sculpture absent or fine commarginal lirae. Lunule and escutcheon obscure. Lateral teeth present in right valve. Pallial sinus deep.” (Coan, Scott, and Bernard, 2000, p. 400)

Tellina (Angulus) vorbei M.A. Hanna, plate 1, figure 1; Plate 1; Plate 1 captions

Tellina vorbei M.A. Hanna, 1927, p. 292, pl. 40, figs. 9, 11, 16. Clark, 1929, Pl. 1, fig. 8.

Original description.—“Left valve; shell of moderate size, fairly thin, not well inflated, roughly equilaterally triangular; ventral margin broadly regularly rounded; posterior dorsal margin straight near the beak, but regularly rounded to the ventral; anterior dorsal margin angulate, but straight on either side of the angulation, angulation due to the lateral laminae on the hinge plate; anterior margin regularly rounded; beak not prominent, extending only slightly beyond the anterior posterior dorsal angulation; ornamentation consists of very fine concentric growth lines; interior of the type not seen.

“Hinge, right valve, very narrow; dentition normal, anterior cardinal only moderately prominent, posterior cardinal bifid but broken in cleaning, anterior laminae very large and responsible for the angulation of the anterior magin; interior of the shell not seen.”

Holotype.—UCMP 30984.

Type locality.—UC 5074. Soledad Canyon, 1 1/4 miles southeast of Sorrento Station, La Jolla Quad., San Diego County, Calif.

Comparison.—Tellina vorbei ***can be recognized by its shape. It resembles Tellina howardi Dickerson most closely, but has a much greater altitude.” (M.A. Hanna, 1927, p. 292).

Geographic range.—Southern California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: Rose Canyon Shale (Keen and Bentson, 1944).

Tellina (Angulus) carpenteri Dall, plate 1, figure 2; Plate 1; Plate 1 captions

Angulus variegatus Carpenter, 1864, p. 611, 627, 639. Not Tellina variegata Gmelin, 1791.

Tellina (Angulus) carpenteri Dall, 1900, p. 303, 320, new name.

Tellina (Moerella) carpenteri Dall. Palmer, 1958, p. 104, pl. 13, figs. 12-16. Hertlein, and Grant, 1972, p. 288-289, pl. 53, figs. 1, 7, 15; pl. 56, fig. 14.

Tellina (Angulus) carpenteri Dall. Coan, Scott, and Bernard, 2000, p. 400, pl. 83.

Original description.—“ Shape of obtusus: no callus; rayed with pink and yellow. 20-60 fm. Cpr. [Carpenter]”

Syntypes.—USNM 15467.

Type locality—“either Neah Bay, Washington, or Catalina Island, California.” (Palmer, 1958, p. 104)

Supplementary description.—“ The pallial sinus ascends from the posterior adductor impression to a rounded point then slopes anteriorly forming an elliptical end which does not quite touch the anterior adductor impression, then slopes posteriorly a short distance and joins the pallial line.

“There is variation in the outline of this species as was indicated by the specific name originally assigned to this species by Carpenter.” (Hertlein and Grant, 1972, p. 289)

“Shell ovate-elongate, inflated.***Internal radial strengthing rib lacking. Sculpture absent or of fine irregular commarginal striae.” (Coan, Scott, and Bernard, 2000, p. 400)

Comparison.—“ Many specimens agree exactly with typical T. carpenteri, other large ones approach in outline the more quadrate form, T. arenica Hertlein and Strong***a generally more southern form which may be a southern subspecies of the present one. Some specimens bear a general resemblance to Tellina (Oudardia) buttoni Dall but they lack the narrow elevated ridge on the interior of the anterior portion of the valves of that species.” (Hertlein and Grant, 1972, p. 289)

Geographic range.—Living: Alaska to Bahía Conceptíon, Baja California Sur; Fossil: Southern California.

Geologic range.—Pliocene to Holocene.

Occurrence in California.—Pliocene: San Diego Formation (Hertlein and Grant, 1972).

Habitat.—In the intertidal zone to 823 m, in most types of sediment. (Coan, Scott, and Bernard, 2000, p. 400)

Tellina (Angulus) meropsis Dall, plate 1, figure 3; Plate 1; Plate 1 captions

Tellina (Moerella) meropsis Dall, 1900b, p. 303, 317, pl. 3, fig. 1. Grant and Gale, 1931, p. 359, pl. 14, figs. 9a-b; pl. 20., figs. 9a-b.

Original description.—“Shell small, white, solid, subequilateral, rather swollen, slightly flexed behind, with a rather bluntly pointed posterior end; surface finely concentrically closely striate, with obscure radial striations and a papery periostracum, which sometimes has an iridescent effect and is often dehiscent; beaks low and pointed; interior white, sometimes with a pale yellow suffusion; hinge normal, the left anterior lateral small but distinct; pallial sinus large, separated from the anterior adductor scar only by the feeble slightly elevated ray. Lon. 15, alt. 11.5, diam. 6.4 mm.”

Holotype.—USNM 123410.

Type locality.—San Diego, Calif. Holocene.

Supplementary description.—“Shell subtrigonal, inflated; posterior end truncate, with an inconspicuous fold. Sculpture absent or of weak commarginal striae.” (Coan, Scott, and Bernard, 2000)

Comparison.—“***similar to the Caribbean T. (Angulus) mera Say, but is more rounded, shorter posteriorly, and heavier.” (Coan, Scott, and Bernard, 2000).

Geographic range.—Southern California to Baja California Norte; living: middle California to Ecuador.

Geologic range.—Pliocene to Holocene.

Occurrence in the Californias.—Pliocene: Golfo de California (Emerson and Hertlein, 1964); Pliocene and Plesitocene: Saugus Formation (Waterfall, 1929); Pleistocene: Unnamed sediments, Mission Bay, Calif. (Grant and Gale, 1931; Kanakoff and Emerson, 1959).

Habitat.—“in the intertidal zone to 50 m, usually in sand, in bays on protected coasts.” (Coan, Scott, and Bernard, 2000).

Tellina (Angulus) modesta (Carpenter), plate 1, figures 4a-d; Plate 1; Plate 1 captions

Angulus modestus Carpenter, 1864c, p. 681; 1865e, p. 56.

Tellina (Oudardia) buttoni Dall, 1900b, p. 320, pl. 4, figs. 12, 13.

Tellina (Angulus) modesta (Carpenter). I.S. Oldroyd, 1924, p. 51. Grant and Gale, 1931, p. 361. Coan, Scott, and Bernard, 2000, p. 402, pl. 83.

Tellina (Oudardia) modesta (Carpenter). Palmer, 1958, p. 103, pl. 13, figs. 4-9.

Original description.—“Angulus modestus, n.s., but closely allied to the eastern A. tener, Say. Two sp. living.” (Carpenter, 1864b, p. 602) “Angulus modestus, n.s. (Subg. of Tellina.) Like tener, Say, but with callus between mantle-bend and scar.” (Carpenter, 1864b, p. 639)

Syntypes.—USNM 4245.

Type locality.—Holocene. Puget Sound, Washington.

Supplementary description.—“Shell subtrigonal, inflated; posterior end truncate, with an inconspicuous fold. Sculpture absent or of weak commarginal striae.” (Coan, Scott, and Bernard, 2000)

Comparison.—It is similar to the Caribbean T. (Angulus) mera Say, 1834, but is more rounded, shorter posteriorly, and heavier.” (Coan, Scott, and Bernard, 2000)

Geographic range.—Living: Puget Sound, Washington to Santa Elena, Ecuador; fossil: Southern California.

Geologic range.—Pliocene to Holocene.

Occurrence in California.—Pliocene and Pleistocene: Saugus Formation (Waterfall, 1929, as buttoni); Pleistocene: Unnamed sediments in Baja California Norte (Emerson, 1956, as buttoni).

Habitat.—In the intertidal zone to 100 m, usually in fine sediments, sandy, in bays or open coasts.” (Coan, Scott, and Bernard, 2000, p. 402)

Subgenus ANGULUS?

Tellina (Angulus?) packardi Dickerson, plate 1, figure 5; Plate 1; Plate 1 captions

Tellina packardi Dickerson, 1914, p. 137, pl. 11, fig. 11.

Original description.—“Shell large, nearly equilateral, compressed; anterior end evenly rounded; posterior end angulated in middle; beak central, small; sides making an angle of 110° at the umbo; anterior dorsal margin slightly convex with abrupt slope nearly equal to that of the straight posterior dorsal margin; ventral margin broadly rounded; surface marked by concentric lines of growth.”

Holotype.—UCMP 11739.

Type locality.—UC 784. Near Lower Lake, at old brick yard, 1/4 mile east of village, NW 1/4, NE 1/4, T. 12 N., R. 7 W., Lake County, Calif.

Comparison.—“This species [T. packardi] differs from T. parilis Gabb, T. aequalis Gabb, and T. lorenzoensis Arnold in its smaller umbonal angle and in its proportionally greater height.” (Dickerson, 1914, p. 137)

Geographic range.—Northern and middle California.

Geologic age.—Paleocene.

Occurrence in California.—Paleocene: Martinez Formation (Dickerson, 1914).

Tellina (Angulus?) joaquinensis Arnold, plate 4, figure 11; Plate 4; Plate 4 captions

Tellina joaquinensis Arnold 1910, p. 49, pl. 2, fig. 11. Arnold and Anderson, 1910, pl. 24, fig. 11. Vokes, 1939, p. 90, pl. 14, figs. 15, 19, 20.

Original description.—“Shell attaining a length of 22 millimeters, oblong, compressed, inequivalve, inequilateral. Beaks slightly posterior, small; anterior extremity regularly rounded; posterior extremity more attenuated than anterior, the posterior dorsal margin sloping from beaks at a somewhat steeper angle than the anterior dorsal margin; posterior fold practically obsolete. Surface smooth, except for numerous very fine lines of growth. Hinge and interior unknown.”

Holotype.—USNM 165619.

Type locality.—USGS 4801. Northwest of Coalinga 3 miles, at San Joaquin Valley coal mine, in NW 1/4 sec. 26, T 20 S., R 14 E, Coalinga Quad., Fresno Co., Calif. Domengine Formation.

Supplementary description.—“This small species reminds one somewhat of Angulus, but is more nearly equilateral and has a less attenuated posterior extremity. T. joaquinensis is characterized and may be distinguished from other California Eocene species by its small size, approximate bilateral symmetry, and the moderately steep slopes of its dorsal margins.” (Arnold, 1910)

Geographic range.—Middle California.

Geologic range.—Paleocene to Eocene.

Occurrence in California.—Paleocene: Meganos Formation (Clark and Woodford, 1927); Eocene: Domengine (Keen and Bentson, 1944), Matilija (Squires, 1999), and Tejon (Dickerson, 1916) Formations.

Tellina (Angulus?) longa Gabb, plate 1, figures 6a, b; Plate 1; Plate 1 captions

Tellina longa Gabb, 1864, p. 155, pl. 22, fig. 131. Anderson and Hanna, 1925, p. 156. Clark and Woodford, 1927, p. 100, pl. 17, figs. 12, 13. Stewart, 1930, p. 199-200, pl. 10, fig. 5.

Original description.—“Shell elongate, slender, compressed; beaks small, sharp, rather prominent, nearly central; anterior cardinal margin sloping, nearly straight; posterior slightly excavated; posterior end rostrate, subangular; anterior end rounded; basal margin convex, most prominent anteriorly, and sloping upwards to the posterior end nearly straight; shell a little more than twice as long as wide. Surface marked by numerous microscopic, concentric lines, generally somewhat irregular. Muscular scars deep; pallial sinus broad, shallow.”

Holotype.—Missing; paratype MCZ 15037.

Type locality.—Near Martinez, Contra Costa County, Calif. Meganos Formation.

Supplementary description.—“Assuming that we have Gabb’s species***the valves are unequal, the right being flatter than the left; the posterior end deflected to the right so that the exterior of the left valve is markedly convex at the posterior end, while the exterior of the right valve is somewhat concave; hinge delicate, with cardinals and laterals well developed. The principal individual variation of the species is in the ratio of the length to the height.” (Clark and Woodford, 1927, p. 100)

Geographic range.—Middle California.

Geologic range.—Paleocene and Eocene.

Occurrence in California.—Paleocene and Eocene: Meganos Formation (Clark and Woodford, 1927); Eocene: Tejon Formation (Arnold, 1906); Eocene to Miocene: Sespe Formation (Eldridge and Arnold, 1907).

Tellina (Angulus?) simiensis Nelson, plate 1, figures 7a, b; Plate 1; Plate 1 captions

Tellina simiensis Nelson, 1925, p. 408, p.153, fig. 1, 2.

Original description.—“Shell rather small, thin, compressed; beaks inconspicuous, posterior central, dorsal edges meeting at an angle of approximately 50° at umbo. Anterior dorsal margin rather broadly convex, faintly excavated in front of beaks; posterior dorsal edge slightly convex; anterior extremity broadly rounded, meeting ventral edge with a slight decrease in curvature; posterior extremity narrowly rounded; ventral edge broadly arcuate. Surface of shell ornamented by numerous fine concentric ridges which merge into a smooth surface toward the beaks.”

Holotype.—UCMP 30522.

Type locality.—UC 3778. South of Simi Valley, Calabasas Quad., SE 1/4, SW 1/4, sec. 23, T. 2 N., R. 18 W., Ventura County, Calif. (Keen and Bentson, 1944) Martinez Formation.

Comparison.—Tellina simiensis “is a higher form than Tellina parilis Gabb. It has a larger umbonal angle and a lesser proportional height than T. Packardi Dickerson and differs in outline from T. herdonensis Dickerson. It lacks also the marked rounded ridge almost parallel to the posterior dorsal margin possessed by T. herdonnnensis.” (Nelson, 1925, p. 408)

Geographic occurrence.—Southern California.

Geologic occurrence.—Paleocene and Eocene.

Occurrence in California.—Paleocene and Eocene: Santa Susana Formation (Zinsmeister, 1983).

Tellina (Angulus?) castacana Anderson and Hanna, plate 1, figure 8; Plate 1; Plate 1 captions

Tellina castacana Anderson and GD. Hanna, 1925, p. 153, pl. 2, fig. 13. Weaver, 1943, p. 198, pl. 51, fig. 2.

Original description.-“Shell small, thin, and inconspicuous; the anterior dorsal slope straight; basal margin almost straight; upper and lower marginal lines almost parallel, or the prolongation of them forming a very acute angle; anterior end regularly rounded; posterior end truncate, very slightly convex; angle at beak about 143°; posterior and basal margins meeting in an angle of about 50°; surface sculptured with fine, flat-topped, concentric ridges which are twice as wide on the anterior end as on the posterior; posterior slope flat, separated from remainder of surface by a sharp angle, in front of which, and near the margin is a shallow depression.”

Holotype.—CAS 796.

Type locality.—CAS 244. Live Oak Creek, Kern County, California. Tejon Formation, Eocene.

Geographic range.—Coos Bay, Oregon, and middle California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: Tejon Formation (Anderson and GD. Hanna, 1925).

Tellina (Angulus?) domenginensis Vokes, plate 1, figure 12

Tellina domenginensis Vokes, 1939, p. 91, pl. 14, figs. 12, 14, 16, 18.

Original description.—“Shell elongate-ovate, thin; umbos small, central; anterior dorsal margin straight to slightly convex, the anterior margin broadly rounded, subtruncate, the ventral margin regularly rounded, the posterior margin sharply rounded, subangulate; posterior dorsal margin straight; umbonal angle 145 degrees; surface-ornamentation consisting only of coarse concentric lines of growth.”

Holotype.—UCMP 15694.

Type locality.—UC 3315. Immediately south of Domengine Creek, Coalinga Quad., Fresno Co., Calif. Domengine Formation.

Comparison.—Tellina domenginensis***most nearly resembles T. jollaensis Dickerson***from which it may be distinguished by its central umbos and its greater umbonal angle***and in its less pointed posterior margin. (Vokes, 1939, p. 91)

Geographic range.— Middle California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: Domengine Formation (Vokes, 1939).

Tellina (Angulus?) jollaensis Dickerson, plate 1, figure 10; Plate 1; Plate 1 captions

Tellina jollaensis Dickerson, 1916, p. 487, pl. 37, fig. 3. M.A. Hanna, 1927. p. 290, pl. 40, fig. 5. Weaver, 1943, p. 197, pl. 48, fig. 3.

Original description.—“Shell small, thin, with subcentral rounded beak; posterior dorsal margin with moderate slope to a pointed posterior; anterior dorsal margin with but a slight slope to a rounded anterior; ventral margin very broadly rounded; decoration consisting of fine lines of growth only.”

Holotype.—UCMP 33252.

Type locality.—UC 2226. Rose Canyon, Lat. 32°50’ N, long. 117°14’W, La Jolla Quad., San Diego Co., Calif. Rose Canyon Shale.

Geographic range.—Southwestern Oregon? (Turner, 1938) and southern California.

Geologic range.—Eocene

Occurrence in California.—Eocene: Rose Canyon Shale (Keen and Bentson, 1944).

Tellina (Angulus?) scrippsensis M.A. Hanna, plate 1, figure 9; Plate 1; Plate 1 captions

Tellina scrippsensis M.A. Hanna, 1927, p. 291, pl. 40, figs. 3, 4, 6, 8, 10, 13.

Original description.—“Left valve: shell very small, thin, only moderately inflated; broadly trigonal; ventral margin broadly regularly rounded; posterior dorsal margin nearly straight; anterior dorsal nearly straight; posterior and anterior margins rather sharply rounded with the latter sharper; beak small, slightly posterior to the center, and projecting only a short way above the dorsal outline; ornamentation consists only of very fine growth lines; hinge margin very narrow; cardinal directly under the beak prominent, probably bifid, bordered on either side by deep sockets; laterals small, not well developed; interior of shell not seen.”

Holotype.—UCMP 31022.

Type locality.—UC 5062. In sea cliff south of mouth of Soledad Valley, due west of midpoint between p and u of Pueblo, La Jolla sheet, San Diego County, Calif. Rose Canyon Shale.

Comparison.—“Tellina scrippsensis***most closely resembles Tellina longa Gabb in being elongate, but is smaller and differs in the general shape.” (M.A. Hanna, 1927, p. 291)

Geographic range.—Southern California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: Rose Canyon Shale (Keen and Bentson, 1944).

Tellina (Angulus?) diabloensis Clark, plate 1, figure 11; Plate 1; Plate 1 captions

Tellina? diabloensis Clark, 1915, p. 471, pl. 61, fig. 5.

Original description.—“Shell subtrigonal to quadrate in outline, subrostrate posteriorly, more ventricose posteriorly than anteriorly. Beak inconspicuous, posterior to center. Anterior dorsal edge very gently curved; posterior dorsal edge straight; ventral edge regularly rounded, rather convex; posterior end bluntly pointed; anterior end broadly and evenly rounded. Surface covered by fairly prominent irregular incremental lines, depressed along the posterior dorsal margin but with no well defined line marking the anterior edge of depression. Ligamental groove short; hinge plate fairly heavy, with well-developed nymph resembling that on a Sanguinolaria; one prominent bifid posterior cardinal tooth; anterior cardinal either obsolete or broken. Anterior to the beak there is an elongate lateral tooth; the distance between the lateral tooth and the anterior dorsal edge suggests that there was a lateral on the left valve which fitted in between the two.”

Holotype.—UCMP 11531.

Type locality.—UC 1478. Southeast of town of Walnut Creek, Concord Quad., Contra Costa County, Calif. San Pablo Formation, Miocene.

Geographic range.—Middle California.

Geologic range.—Miocene: San Pablo Formation (Clark, 1915).

Occurrence in California.—Miocene: San Pablo (Clark, 1915) and Santa Margarita (Addicott and others, 1978) Formations.

Tellina (Angulus?) woodringi Adegoke, plate 2, figure 1; Plate 2; Plate 2 captions

Tellina? cf. T.? oldroydi Wiedey. Woodring and others, 1940, p. 92, pl. 33, fig. 5; pl. 14, fig. 8.

“Tellina” woodringi Adegoke, 1969, p. 132-133, pl. 8, figs. 1, 4-6.

Original description.—“Shell large sized, moderately thick, very elongate, oval, inequivalve and inequilateral; left valve more inflated and gently arched than right valve, the latter with prominent broad depression from anterior of umbo to middle of ventral margin; anterior dorsal margin long, gently arcuate; posterior dorsal margin straight or slightly depressed, slightly longer than anterior dorsal margin; beaks slightly posterior; anterior ventral margin fairly broadly rounded; posterior dorsal margin forms broadly acute junction with rather gently rounded ventral margin; surface onamented [ornamented] by incremental lines of growth.”

Holotype.—UCMP 36771.

Type locality.—UCD-1193. T. 22 S., R. 16 E., sec. 22; 360 feet north, 475 feet east, Reef Ridge Quadrangle, California. San Joaquin Formation.

Comparison.—The new species [“T”. woodringi”] may be readily distinguished from other Tertiary species by its large size and the relatively high and elongate valves. It is more inflated than the Recent species, T. lutea Gray.” (Adeoke, 1969, p. 133)

Geographic range.—Middle to southern California.

Geologic range.—Miocene and Pliocene.

Occurrence in California.—Miocene and Pliocene: Etchegoin Formation (Adegoke, 1969); Pliocene: San Joaquin Formation (Adegoke, 1969).

Subgenus SAULELLA Zinsmeister, 1983

“Medium-sized, thin, slightly convex, inequilaeral shell with prominent, low, concentric undulations; dorsal posterior margin sloping at a moderate angle giving the posterior half of the shell a tapered profile; ligament exturnal with prominent buttress; hinge of left valve with two small cardinal teeth connected, forming an inverted V, 2a slightly bifid; lateral teeth absent.”

Geographic range.—California to Baja California.

Geologic range.—Paleocene.

Tellina (Saulella) undulifera Gabb, plate 2, figures 2a,b; Plate 2; Plate 2 captions

Tellina undulifera Gabb, 1869, p. 183, pl. 30, fig. 74. Dickerson, 1914, p. 151, pl. 11, figs. 7a, 7b. Clark, 1929, pl. 1, fig. 8. Schenck and Keen, 1940, pl. 19, fig. 3.

Tellina (?) undulifera Gabb. Nelson, 1925b, p. 415, pl. 53, figs. 8a, 8b.

“Tellina?” undulifera Gabb. Stewart, 1930, p. 204-205, pl. 7, fig. 8.

Saulella undulifera (Gabb). Zinsmeister, 1983, p. 1288, Fig. 1 I,J.

Original description.—“Shell moderately large, thin, slightly convex, very inequilateral, broadly rounded in advance, tapering behind; beaks 2/5 of the length from the anterior end, slightly pointed in advance; cardinal margin sloping rapidly and with a slight convexity to the posterior end, which is narrowly rounded; base prominently convex. Surface marked by concentric ribs, forming towards the base.”

Lectotype.—ANSP 4551 (Stewart, 1930).

Type locality.—West of Martinez, Carquinex Quad., Contra Costa County, Calif. (Keen and Bentson, 1944) Martinez Formation.

Supplementary description.—“The shell is, in all cases, so softened by decomposition that I am unable, in any of the specimens, to expose the hinge, and therefore refer the species to the above genus with some hesitation. Judging from the imperfect impressions left on some internal casts, the hinge has been very delicate, and seems more like that of a Tellina than of any other genus, the exterior form and general appearance render this determination somewhat doubtful.” (Gabb, 1869, p. 183)

Comparison.—”In outline the shell is not unlike T. ooides, but the posterior end is narrower, the beaks are more prominent, the surface is more convex, and the style of ornament will serve at once to distinguish the two species.” (Gabb, 1869, p. 183)

Geographic range.—California to Baja California (Zinsmeister, 1983, p. 1288).

Geologic range.—Paleocene.

Occurrence in California.—Paleocene: Martinez Formation (Arnold, 1906; Dickerson, 1914; Keen and Bentson, 1944; Kew, 1924).

Subgenus CADELLA Dall, Bartsch, and Rehder, 1938

“Shell thick, inflated, subequivalve, ovate to subquadrate. Sculpture absent or of feeble commarginal striae. Lunule small, narrow, predominantly in left valve; escutcheon weak. Two strong lateral teeth present in right valve. Pallial sinus deep.” (Coan, Scott, and Bernard, 2000, p. 402)

Geographic range.—Living: Indo-Pacific and eastern Pacific from Bering Sea to Baja California Norte; fossil: middle and southern California.

Geologic range.—Miocene to Holocene.

Tellina (Cadella) nuculoides (Reeve), plate 2, figure 3; Plate 2; Plate 2 captions

Donax nuculoides Reeve, 1854, pl. 8.

Tellina (Cadella) nuculoides (Reeve). Coan, Scott, and Bernard, 2000, p. 403, pl. 83.

Maera salmonea Carpenter, 1864, p. 627, 639.

Tellina salmonea Carpenter. Packard, 1918, p. 276, pl. 25, figs. 3a-b. I.S. Oldroyd, 1924, p. 165, pl. 44, figs.3a-b. Adegoke, 1969, p. 130.

Tellina (Cadella) salmonea Carpenter. Arnold, 1903, p. 157, pl. 13, fig. 7. Palmer, 1958, p. 105, pl. 13, figs. 17-19. Hertlein and Grant, 1972, p. 286-287, pl. 53, figs. 2-4, 8, 16.

Original description.—“Small, subquadrate, glossy, salmon-tinted. Beach-20 fm.”
Figured specimen.—SBMNH 43172.

Supplementary description.—“Shell inflated, thick for size, subtrigonal. Sculpture absent, with occasional growth checks.***Length to 20 mm.” (Coan, Scott, and Bernard, 2000)

Geographic range.—Living: Bering Sea to Baja California Sur; fossil: Southern California.

Geologic range.—Oligocene to Holocene.

Occurrence in California.—Oligocene and Miocene: Temblor Formation (Adegoke, 1969); Miocene: Cierbo Sandstone, San Pablo Group (Clark, 1915; Hertlein and grant, 1972) and McClure Shale Member, Monterey Formation (Adegoke, 1969); Pliocene: San Diego Formation (Hertlein and Grant, 1972); Pliocene and Pleistocene: Fernando Formation (Kennedy, 1975).

Habitat.—“***in the intertidal zone to 75 m, usually in coarse sand, but also found in a wide variety of sediments and rock.” (Coan, Scott, and Bernard, 2000)

Subgenus CADELLA?

Tellina (Cadella?) californica Gabb, plate 2, figure 4; Plate 2; Plate 2 captions

Tellina californica Gabb, 1864, p. 161, pl. 30, fig. 245. Clark and Woodford, 1927, p. 99, pl. 17, fig. 16.

Not Tellina californica Dickerson, 1915, pl. 4, fig. 3. See Macoma viticola Anderson and GD. Hanna.

Original description.—“Shell small, very inequilateral; beaks prominent a little behind the middle of the shell; posterior margin abruptly truncated obliquely from the beaks to the base; anterior end very prominent and rounded base slightly sinuous. Surface slightly convex and marked by very fine lines of growth.”

Holotype.—Missing.

Type locality.—Marsh’s east of Mt. Diablo, California. Meganos Formation, Paleocene and Eocene.

Supplementary description.—“Shell small, very inequilateral; beaks prominent, a little behind the middle of the shell; posterior margin abruptly truncated obliquely from the beaks to the base; anterior end very prominent and rounded; base slightly sinuous. Surface slightly convex and marked by very fine lines of growth.” (Clark and Woodford, 1927, p. 99)

Geographic range.—Middle California.

Geologic range.—Paleocene and Eocene.

Occurrence in California.—Paleocene and Eocene: Meganos Formation (Clark and Woodford, 1927).

Tellina (Cadella?) congesta Conrad, plate 4, figures 10a, b; Plate 4; Plate 4 captions

Tellina congesta Conrad, 1855, p. 12. Conrad, 1857, pl. 3, figs. 14, 18, 21, 21a. Dall, 1909, p. 166.

Original description.—“Subtriangular, ventricose, inequilateral; anterior margin obliquely truncated; anterior basal margin subrectilinear, oblique, extremity angulated, much above the line of the base; posterior margin and posterior basal margin regularly rounded.”

Holotype.— USNM 1849.

Type locality.—Monterey, Monterey County, Calif. Monterey Formation, Miocene.

Geographic range.—Middle California.

Geologic range.—Miocene.

Occurrence in California.—Miocene: Monterey (Arnold, 1906; Addicott and others, 1978; D.L. Durham, 1966) and Santa Margarita (Addicott and others, 1978) Formations.

Subgenus ELLIPTOTELLINA Cossmann, 1887

“Near T. (Tellinella) but smaller, with lateral teeth weak or wanting in LV.” (Moore, 1969, p. 615)

Geographic range.—Europe; California?

Geologic range.—Eocene; Oligocene?

Subgenus ELLIPTOTELLINA?

Tellina (Elliptotellina?) townsendensis Clark, plate 2, figure 5; Plate 2; Plate 2 captions

Tellina townsendensis Clark, 1925, p. 94, pl. 12, figs. 11, 12.

Tellina (Tellina) townsendensis Clark. Effinger, 1938, p. 371, pl. 46, fig. 14.

Tellina oregonensis Conrad. Dickerson, 1917, p. 160, pl. 29, fig. 4. Not Tellina oregonensis Conrad, 1848.

Original description.—“Shell elongate ovate in outline; beaks posterior to middle of valve. Anterior end regularly rounded; anterior dorsal margin long and gently convex; posterior dorsal edge straight to end of ligamental groove; from this point on, edge becomes broadly and gently convex; posterior end truncated. Surface of right valve with a sharply depressed posterior dorsal margin separated from main surface of shell by a distinct line, which connects the beaks with lower angle of truncated end. Surface of shell smooth. Left valve and hinge unknown.”

Holotype.—SU5208.

Type locality.—UW 59. On Fossil Creek 3 miles above junction with Grays River, Washington. Gries Ranch Formation.

Geographic range.—Southern California and Washington.

Geologic range.—Eocene to Oligocene.

Occurrence in California.—Eocene and Oligocene: San Emigdio Formation (DeLise, 1967)

Subgenus EURYTELLINA Fischer, 1887

“Medium-sized, elongate, posterior end not rostrate; sculpture concentric;***laterals in LV not as strong as in RV, anterior laterals close to cardinals, posterior distant; pallial sinus confluent with pallial line, approaching or touching anterior adductor.” (Moore, 1969, p. N615)

“Most are elongate and concentrically sculptured***the lateral teeth are weak or wanting in the left valve.” (Keen, 1971, p. 215)

Geographic range.—Eastern and western North America and South America.

Geologic range.—Miocene to Holocene.

Subgenus EURYTELLINA?

Tellina (Eurytellina?) herndonensis Dickerson, plate 2, figure 6; Plate 2; Plate 2 captions

Tellina herndonensis Dickerson, 1914, p. 136-137, pl. 11, fig. 9.

Original description.—“Shell moderate in size, longer than high; beaks nearly central, prominent. Posterior dorsal margin, straight with slightly greater slope than the posterior[anterior?] dorsal margin. Posterior end narrowly rounded; anterior broadly rounded; ventral margin nearly straight. A marked, rounded ridge nearly parallels the posterior dorsal margin.”

Holotype.—UCMP 33262.

Type locality.—UC 784. Near Lower Lake, at old brick yard 1/4 mile east of village, NE 1/4, NE 1/4 sec. 11, T. 12 N., R. 7 W., Lake Co., Calif. Martinez Formation.

Geographic range.—Northern and middle California.

Geologic range.—Paleocene.

Occurrence in California.—Paleocene: Martinez Formation (Dickerson, 1914).

Tellina (Eurytellina?) martinezensis Weaver, plate 2, figure 7; Plate 2; Plate 2 captions

Tellina martinezensis Weaver, 1905, p. 115-116, pl. 12, fig. 3.

Original description.—“The shell is small, thin, compressed, and about twice as long as the distance from the beak to the base. The anterior end is rather broad. The posterior end is considerably narrower and truncated obliquely. The beaks are small and nearly central. The basal margin is convex. A ridge especially well marked near the beak but gradually becoming fainter toward the base, passes from the beak to the posterior basal angle. The surface is ornamented by numerous small, regular, concentric lines.”

Holotype.—UCMP 11876.

Type locality.—Two miles south of Martinez, on east side of road to Walnut Creek, Concord Quad., Contra Costa Co., Calif. Martinez Formation.

Geographic range.—Middle California.

Geologic range.—Paleocene.

Occurrence in California.—Paleocene: Martinez Formation (Weaver, 1905).

Tellina (Eurytellina?) lorenzoensis Arnold

Tellina lorenzoensis Arnold, 1908, p. 367, pl. 33, fig. 1. Clark, 1915, p. 15. Clark, 1918, p. 152.

Macoma lorenzoensis (Arnold). Arnold and Hannibal, 1913, p. 587.

Original description.—“Shell attaining a length of 40 mm., width a little over five-eighths of length, oblong, compressed, slightly inequivalve, anterior end evenly rounded, posterior end biangular and narrower than anterior; umbo small, central, though sometimes, as in type, placed a little in front of middle; sides making an angle of 125° at the umbo; anterior dorsal margin very gently curved near umbo, becoming rapidly more curved near extremities; ventral dorsal margin very gently curved for whole length to upper posterior angle; a moderately sharp fold, on which the lines of growth are particularly prominent, extends from the umbo to the lower posterior angle; a faint indication of a reentrant angle often occurs in the margin at the end of the fold; base nearly straight, curving quite rapidly at ends. Surface sculptured by numerous slightly unequal concentric lines. Left valve similar to right except that instead of being very slightly flexed upward at the posterior extremity, it is flexed downward.”

Holotype.—USNM 165439.

Type locality.—UCMP loc. no. 337. Southeast branch of south fork of Waddell Creek, Big Basin, sec. 6, T. 9 S., R. 3 W., Santa Cruz Quad., Santa Cruz Co., Calif. (Keen and Bentson, 1944).

Geographic range.—Middle California.

Geologic range.—Eocene and Oligocene.

Occurrence in California.—Eocene and Oligocene: San Lorenzo Formation (Arnold, 1908; Clark, 1918); Oligocene: Kirker Tuff (Clark, 1918).

Tellina (Eurytellina?) oldroydi Wiedey, plate 2, figure 8; Plate 2; Plate 2 captions

Tellina oldroydi Wiedey, 1928, p. 148-149, pl. 19, fig. 3.

“Tellina” oldroydi Wiedey. Adegoke, 1969, p. 132, pl. 8, fig. 3.

Original description.—“Shell of large size, elongate, and subovate in outline, slightly inequivalve, perceptibly inequilateral, gently inflated, and thin shelled. Anterior dorsal margin long, nearly straight, or slightly convex; anterior dorsal extremity quite sharply rounded, with the basal margin regularly but very broadly rounded. The posterior dorsal extremity is subtruncate, with the margin sloping straight from the beaks at an angle similar to that taken by the anterior dorsal margin. Posterior end gaping and twisted to the right. Umbones not large and only gently elevated. The beaks are situated in the posterior position of the shell, inturned, and pointed posteriorly. The shell is smooth but for the concentric, incremental lines of growth. The posterior portion of the right valve shows a depressed area separated from the main body of the shell by a distinct shoulder, which passes from the beaks to the posterior extremity. On the left valve in the position of the shoulder on the opposite valve, a faint sulcus is developed.”

Holotype.—SDNM 36.

Type locality.—SU 425. Head of small canyon heading westward from head of Dry Canyon at base of east-west ridge forming divide, 2 miles south of Calabasas, Santa Monica Mountains, sec. 34, T. 1 N., R. 17 W., SB, Calabassas Quad., Los Angeles County, Calif. Topanga Formation.

Comparison.—“T. nevadensis***is more elongate anteriorly, less elongate posteriorly, and has a more sharply rounded anterior extremity.” (Wiedey, 1928, p. 148-149)

“This species [“T.” oldroydi] is very similar in outline and size to T. oyoyana Conrad but is more elongate anteriorly and shorter posteriorly. The valves are relatively higher and thicker, and shorter posteriorly than in T. nevadensis Anderson and Martin.” (Adegoke, 1969, p. 132)

Geographic range.—Southern California.

Geologic range.—Oligocene and Miocene.

Ocurrence in California.—Oligocene and Miocene: Temblor Formation (Wiedey, 1928; Adegoke, 1969); Miocene: Round Mountain Silt (Keen, 1943), Santa Margarita (Adegoke, 1969) and Cold Creek Member, Topanga Canyon (T. Susuki, written commun., 1978) Formations.

Tellina (Eurytellina?) hannibali Clark, plate 2, figure 9; Plate 2; Plate 2 captions

Tellina hannibali Clark, 1915, p. 473, pl. 61, fig. 11.

Original description.—“Shell medium in size; beaks inconspicuous posterior to the middle. Anterior dorsal margin nearly straight, becoming slightly convex toward the anterior extremity; posterior dorsal edge slightly convex, the greatest amount of convexity coming just in front of the posterior extremity; posterior extremity pointed; anterior end regularly rounded; ventral edge gently and regularly arcuate. Along the posterior edge there is a narrow depressed margin which is separated from the remaining portion of the surface by a fairly distinct line. Surface smooth, except for irregular incremental lines.”

Holotype.—UCMP 11532.

Type locality.—UC 1942. “Concord quad., 321 mm. E, 193 mm. S of NW corner of sheet, Contra Costa Co.” (Keen and Bentson, 1944), Calif. San Pablo Formation.

Geographic range.—Middle California.

Geologic range.—Miocene.

Occurrence in California.—Miocene: Cierbo and Neroly Sandstones, San Pablo Group (Hall, 1960).

Subgenus LACIOLINA Iredale, 1937

“Somewhat resembling Macoma in shape and in the partially sunken ligament, but hinge with well-developed lateral teeth.” (Keen, 1971, p. 219)

Tellina (Laciolina) ochracea Carpenter, plate 2, figure 10; Plate 2; Plate 2 captions

Tellina (Peronaederma) ochracea Carpenter, 1864, p. 311.

Tellina (Scrobiculina) ochracea Carpenter. Durham, 1950, p. 89, pl. 23, figs. 9, 18.

Tellina (Laciolina) ochracea Carpenter. Keen, 1971, p. 219, fig. 537.

Original description.—

Supplementary description.—“***large, thin shell***Sculpture is of fine concentric striae.” (Keen, 1971, p. 219)

Geographic distribution.—Baja California Sur.

Geologic distribution.—Pliocene to Holocene.

Occurrence in Baja California Sur.—Pliocene: Maquer Formation (Durham, 1950).

Habitat.—On tide flats and offshore at least to 80 m. (Keen, 1971, p. 219)

Subgenus MEGANGULUS Afshar, 1969

“Shell of medium to large size, thick, white, elongate-ovate, compressed, anterior end rounded, posterior end sub-rostrate.The beaks are located slightly posterior to the mid-length; dorsal margins are sloping equally and steeply, ventral margin is broadly arcuate. Postero-umbonal fold is weak; ligament is external and of medium size. The sculpture consists of fine concentric striae. There are two Tellina-type cardinals in each valve, right anterior lateral is situated close to the cardinals and the other laterals are absent. Pallial sinus is small and ventral margin of if it is entirely coalescent with the pallial line.”

Geographic range.—Japan and Sakhalin; California?

Geologic age.—Holocene; Paleocene?

Subgenus MEGANULUS?

Tellina (Megangulus?) crooki Nelson, plate 2, figure 11; Plate 2; Plate 2 captions

Tellina crooki Nelson, 1925, p. 415, pl. 53, fig. 4.

Original description.—“Shell medium-sized, thin, compressed; beaks small, a trifle anterior to center. Dorsal edges meeting at an angle of 130° at umbo. Anterior dorsal edge straight; posterior dorsal edge straight; anterior extremity broadly rounded; posterior extremity bluntly rounded but narrower than anterior extremity; ventral edge regularly arcuate. Surface of shell smooth except for fine irregular growth lines. Length of type specimen, 29.5 mm.; height, 20 mm.; diameter of one valve, about 2.5 mm.”

Holotype.—UCMP 30523.

Type locality.—UCMP loc. no. 3776. West side of bottom of canyon 5300 ft. N 3°W of Hill 2150, Simi Hills, Calabasas Quad., Ventura Co., Calif. Martinez Formation, Paleocene.

Comparison.—“Tellina mathewsoni Gabb differs from T. crooki in having central beaks and a greater proportional length.” (Nelson, 1925)

Geographic range.—Southern California.

Geologic range.—Paleocene.

Occurrence in California.—Paleocene: Martinez Formation (Keen and Bentson, 1944).

Tellina (Megangulus?) kewi Dickerson, plate 2, figure 12; Plate 2; Plate 2 captions

Tellina kewi Dickerson, 1914, p. 138-139, pl. 12, fig. 1.

Original description.—“Shell medium, thin, broad, slightly convex, very inequilateral, but longer than high; beak small, incurved; posterior and anterior dorsal margins nearly straight, the posterior sloping the more abruptly; anterior end very broadly rounded; posterior end produced and pointed; ventral margin broadly rounded, more prominent beneath the beaks, and curving from this point abruptly upward to the pointed posterior end. Surface plain, or marked with simple growth lines.”

Holotype.—UCMP 11715.

Type locality.—UCMP loc. no, 784. Near Lower Lake, at old brick yard 1/4 mile east of village, NW 1/4, NE 1/4, sec. 11, T. 12 N., R. 7 W., Lake County, Calif. Martinez Formation.

Geographic range.—Northern and middle California.

Geologic range.—Paleocene.

Occurrence in California.—Paleocene: Martinez Formation (Dickerson, 1914).

Subgenus OLCESIA Addicott, 1973

“Shell large and heavy. Posterior side longer than anterior side. Posterior portion of valves flex to the right, flexing much stronger in right valve. Surface sculptured by fine concentric lines of growth and very faint radial striae. Anterior dorsal margin broadly convex, posterior margin long and relatively straight. Hinge plate broad and very heavy. Right valve has a long anterior lateral, a weak anterior cardinal, a heavy, bifid main cardinal, and a weak posterior lateral. Left valve has a weak anterior lateral, a simple cardinal, a weak posterior cardinal, and a strong, slightly curved posterior lateral terminating near the base of the hinge plate. Left valve flattened in dorsal aspect, has slight convexity; anterior part of right valve convex, posterior part concave. Right valve has an elongate, weak lunule. Pallial line deeply impressed, extending to base of the anterior muscle scar. Anterior muscle scar elongate, tear shaped; posterior scar subquadrate. Ligament elongate, sunken, base deeply set on hinge plate.” (Addicott, 1973)

Tellina (Olcesia) piercei (Arnold), plate 3, figure 1; Plate 3; Plate 3 captions

Macoma piercei Arnold, 1910, p. 55-56, pl. 7, fig. 6.

Tellina (Olcesia) piercei (Arnold). Addicott, 1973, p. 31-32, pl. 4, figs. 10, 12; pl. 5, figs. 12, 13.

Tellina nevadensis Anderson and Martin, 1914, p. 61-62, pl. 2, figs. 3a-3c.

Original description.—“Shell large for the genus, compressed, inequilateral, inequivalve; beaks prominent; anterior end evenly rounded; ventral margin broadly arcuate; posterior end rostrate and bent to the right, obliquely truncated; posterior dorsal margin straight from the beaks to the truncation: a prominent fold and a concave flexure extending from the umbones to the posterior ventral extremity and bordering the posterior dorsal area in either valve; right valve convex; left valve nearly flat; surface marked with concentric ridges corresponding to the lines of growth and fine radial lines which are invisible on worn specimens; hinge plate narrow, with two cardinal and two lateral teeth in the right valve, and two cardinal teeth in the left valve; the posterior cardinal in the right valve bifid; muscular impressions large and distinct; pallial sinus very deep, extending almost to the anterior adductor; a thickened obscure ray extending diagonally across the anterior portion of the shell behind the anterior adductor.” (nevadensis)

Holotype.—USNM 165595.

Type locality.—USGS 46311, Turritella bed on east flank of high hill northeast of Oil City in SE 1/2,NE1/4 sec. 16, T. 19 S., R. 15 E. Temblor Formation.

Supplementary description.—“This large thick-shelled species is characterized by a very heavy hinge plate that has well-developed lateral teeth. The valves are boat shaped and are pointed posteriorly. On the left valve, the sharp posterior dorsal margin is bordered by a weak ridge, below which is a narrow sulcus; on the right valve, it is bordered by a much stronger sulcus below which occurs a prominent ridge that extends to the posterior extremity.

“***there can be little doubt that it [T. piercei] is iden[t]ical to T. nevadensis owing to the long, deeply excavated ligamental groove, the strong ridge below the posterior dorsal margin, the anteriorly located beak, and the surface sculpture of fine concentric ribs. The types of both species are from stratigraphic units refereable to the ‘Temblor Stage’” (Addicott, 1973)

Comparison.—“The holotype [T. piercei], a left valve , clearly is not allied to M. secta. It lacks the convex posterior dorsal margin characteristic of that species and has an extremely long, deeply set ligamental groove.” (Addicott, 1973, p. 31)

Geographic range.—Middle and southern California.

Geologic range.—Oligocene to Miocene.

Occurrence in California.—Oligocene: Wygal Sandstone Member, Temblor Formation (Addicott, 1973); Miocene: Saltos Shale and Hambre Members, Monterey Formation (Addicott and others, 1978) .

Subgenus OLCESIA?

Tellina (Olcesia?) ocoyana Conrad, plate 3, figure 2; Plate 3; Plate 3 captions

Tellina ocoyana Conrad, 1855, p. 19; 1857, pl. 8, figs. 75, 75a. Loel and Corey, 1932, p. 226, pl. 43, fig. 4. Adegoke, 1969, p. 130-131.

Original description.—“Elliptical compressed, inequilateral; posterior extremity acutely rounded, much above the line of the base; anterior end somewhat acutely rounded; cardinal teeth robust.”

Holotype.—Missing and presumed lost.

Type locality.—“Ocoya Creek, Calif.” [“Probably Poso Cr., NE cor, T 28S, R 28E, Kern Co.” (Keen and Bentson, 1944)] .

“The identity of Conrad’s species may never be satisfactorily determined because the type has apparently been lost (Keen and Bentson, 1944, p. 115) and the original figures appear to be somewhat stylized line drawings that do not indicate the critical details of internal morphology.
Most subsequent records of T. ocoyana are presumed to be of T. piercei.” (Addicott, 1973, p.31-32)

Comparison.—“This species differs from the Recent T. idae Dall, with which it was synonymized by Grant and Gale [1931] by its shorter anterior dorsal margin and the more anterior beak. Also the posterior dorsal margin is longer and the ratio of height to length less than in T. idae.” (Adegoke, 1969)

Adegoke (1969, p. 131) believed that T. nevadensis should not be placed in synonymy with T. ocoyana because the anterior dorsal margin is higher and more broadly rounded. He also believed that the anterior dorsal margin of T. nevadensis is more elongate and the anterior margin more acutely pointed than in T. ocoyana and that T. nevadensis should be regarded as a distinct species. (Adegoke, 1969, p. 131)

Geographic range.—Southern California.

Geologic range.—Oligocene and Miocene.

Occurrence in California.—Oligocene and Miocene: Temblor Formation (Stewart, 1946; Adegoke, 1969); Miocene: Round Mountain Silt (Keen, 1943).

Subgenus OUDARDIA Monterosato, 1884

“Resembling T. (Moerella) in form but with a thick internal rib, radiating from beak to ventral margin in front of mid-line; surface with or without fine oblique lines of sculpture.” (Moore, 1969, p. N619)

Subgenus OUDARDIA?

Tellina (Oudardia?) emacerata Conrad, plate 3, figure 3; Plate 3; Plate 3 captions

Tellina emacerata Conrad, 1849, p. 725, pl. 18, fig. 4. Dall, 1909, p. 125, 154. Weaver, 1943, p. 206, pl. 48, fig. 20, not? pl. 48, fig. 18. Moore, 1963, p. 78-79, pl. 29, figs. 6, 7, 13, 14.

Tellina (Oudardia?) emacerata Conrad. Addicott, 1973, p. 32, pl. 4, fig.11.

Tellina oregonensis Conrad, 1848, p. 432, fig. 5 [nomen dubium, Moore, 1963, p. 79].

Tellina (Peronida) oregonensis Conrad. Etherington, 1931, p. 83-84, pl. 10, figs. 6, 7.

Tellina clallamensis Reagan, 1909, p. 186-187, pl. 2, fig. 18.

Original description.—“Elliptical, much compressed; anterior extremity obliquely truncate, straight from the apex, front reflected; dorsal margin posteriorly declining; posterior margin rounded; inferior margin arcuate. Lateral surface marked with fine, regular, closely arranged, concentric, impressed lines.”

Holotype.—USNM 3494.

Type locality.—Astoria,Oregon.

Supplementary description.—“The type specimen***is thin shelled and has evenly spaced concentric grooves separated by interspaces about five times as wide as the grooves at the anterior ventral margin, but tending to become more closely spaced towards the anterior dorsal margin and the posterior margin, until the grooves are separated by interspaces of equal width. There is a conspicuous flattened angulation near the posterior margin which has concentric ridges. These ridges seem to be the continuation of the concentric grooves on the rest of the shell, which change direction abruptly at the angulation and trend towards the posterior dorsal margin at an angle of about 45°.” (Moore, 1963)

Geographic range.—Washington to middle California.

Geologic range.—Oligocene to Miocene.

Occurrence in California.—Oligocene: Wygal Sandstone Member, Temblor Formation (Addicott, 1973); Miocene: Briones Sandstone, San Pablo Group (Trask, 1922).

Subgenus PERONIDIA Dall, 1900

“Shell elongate, solid, compressed, subequivalve. Lunule absent; escutcheon long, narrow. Sculpture of fine commarginal ribs or grooves. Lateral teeth feeble.” (Coan, Scott, and Bernard, 2000)

Tellina (Peronidia) bodegensis Hinds, plate 3, figure 4; Plate 3; Plate 3 captions

Tellina bodegensis Hinds, 1845, p. 67, pl. 21, fig. 2. Dall, 1900b, p. 320, pl. 4, figs. 12, 13. Keen, 1966, p. 267. Adegoke, 1969, p. 132.

Tellina (Angulus) bodegensis Hinds. Arnold, 1903, p. 158, pl. 15, fig. 7.

Tellina (Peronidia) bodegensis Hinds. Dall, 1900b, p. 304. I.S. Oldroyd, 1924, p. 168, pl. 44, fig. 5. Hertlein and Grant, 1972, p. 289-290, pl. 53, figs. 9, 18. Coan, Scott, and Bernard, 2000, p. 404, pl. 84.

Original description.—“Shell of medium size, elongated, narrow-ovate, rather thick; umbones posterior to the center and pointing posteriorly; anterior portion of the shell evenly rounded, the dorsal and ventral lines being nearly parallel; posterior dorsal margin depressed back of umbone, running off quite obliquely to a line which truncates the posterior end near the base; basal posterior angle nearly a right angle; basal line nearly straight; a prominent bifid cardinal tooth on each valve; pallial sinus long and narrow; generally thickened anteriorly.”

Holotype.— BM(NH) 74.12.11.372.

Type locality.—Bodegas Bay, Calif. Holocene in 13 m.

Supplementary description.—“Shell thick, solid, subelliptical, longer anteriorly; sculpture of closely spaced commarginal ridges; exterior polished***”(Coan, Scott, and Bernard, 2000).

Comparison.—“Similar to lutea, but the beaks are posterior to the center.” (Abbott, 1974).

“Tellina bodegensis differs from T. santarosae Dall in that the shell is thicker more convex, less equilateral, higher in proportion to the length, the concentric sculpture is less evenly spaced and the pallial sinus is broader.” (Hertlein and Grant, 1972, p. 290)

Geographic range.—Living: Sitka, Alaska to Bahía Magdalena, Baja California Sur (Coan, Scott, and Bernard, 2000).

Geologic range.—Miocene to Holocene.

Occurrence in the Californias.—Miocene and Pliocene: Etchegoin Formation (Nomland, 1917a; Adegoke, 1969); Pliocene: San Diego Formation (Nomland, 1917a); Pliocene and Pleistocene: Fernando (Kennedy, 1975), Merced (Martin, 1914), San Pedro (Arnold, 1903), Saugus (Waterfall, 1929), and Wildcat Formations (Martin, 1914; Faustman, 1964); Unnamed Pleistocene sediments at Bahía Magdalena (Jordan, 1924) and San Quintin (Jordan, 1936).

Habitat.—On sandy beaches along the outer coast and particularly in the coarse, shifting sand near the entrances to bays, lagoons, and estuaries. (Fitch, 1953). In the intertidal zone to 100 m in sand, usually in exposed situations (Coan, Scott, and Bernard, 2000).

Subgenus PERONIDA?

Tellina (Peronidia?) aragonia Dall, plate 3, figure 5; Plate 3; Plate 3 captions

Tellina aragonia Dall, 1909, p. 124-125, pl. 14, fig. 3. Arnold, 1910, p. 134, pl. 14, fig. 2. Howe, 1922, p. 92. Grant and Gale, 1931, p. 358. Adegoke, 1969, p. 132, pl. 8, fig. 2.

Original description.—“Shell elongate, compressed, subequilateral, slightly inequivalve; beaks low, slightly behind the middle of the shell; right valve a little flatter than the other, with the rostrated posterior part of the shell somewhat bent to the right; dorsal slopes subequally oblique, the anterior slightly arcuate, the posterior slightly excavated; ligament strong on strong nymphs about (in the type) 15 mm. long; posterior end subrostrate, bluntly pointed below, with an obscure ridge from the beak forming on the right valve a narrow dorsal area; anterior end evenly rounded, base gently arcuate; surface smooth, finely concentrically grooved, with wider, flattish interspaces, the sculpture strongest in front. Interior inaccessible for the most part but with no indication of any internal umbonal rib.”

Holotype.— USNM 153940.

Type locality.—Coos Bay, Oregon. Empire Formation, Miocene.

Geographic range.—Southern Oregon; middle California.

Geologic range.—Miocene and Pliocene.

Occurrence in California.—Miocene and Pliocene: Etchegoin Formation (Adegoke, 1969).

Subgenus PHYLLODINA Dall, 1900

“With concentric sculpture forming spines along posterior dorsal margin; pallial line not confluent.” (Moore, 1969, p. N619)

Geographic range.—Eastern and western Central America; California.

Geologic range.—Oligocene to Holocene.

Tellina (Phyllodina) pristiphora Dall, plate 3, figure 6; Plate 3; Plate 3 captions

Tellina (Phyllodina) pristiphora Dall, 1900, p. 302, 316, pl. 4, fig. 14. Abbott, 1974, p. 497, fig. 5645. Keen, 1974, p. 223, fig. 546.

Original description.—“Shell compressed, small, the right valve flatter, nearly equilateral; the beaks compressed, acute, low, with the minute prodissoconch and the nepionic shell polished and conspicuous; surface greenish white, chalky, sculptured with evenly spaced elevated concentric lamellae over the posterior third of the shell, with much wider faintly striated interspaces; in the right valve over the anterior two-thirds of the disk the lamellae are obsolete except on the dorsal margin, over the umbonal fold they are conspicuous, interrupted by the sulcus above it, and rise into small squarish foliations on the posterior dorsal margin; on the anterior dorsal margin the prominences are more like serrations; on the left valve there are no lamellae on the disk, but the foliations persist though less prominent; lunule and escutcheon developed between the foliated keels, but very narrow and rather shallow, over all the disk translucent subradial venulations are frequent; interior with the hinge strongly developed, the pallial sinus narrow, obliquely ascending and entirely free from the pallial line below.”

Holotype.—USNM 108575.

Type locality.—Station 2823, near La Paz, Baja California Sur.

Geographic range.—Living: Golfo de California to Costa Rica; fossil: Southern California.

Geologic range.—Miocene to Holocene.

Occurrence in California.—Miocene and Pliocene: Imperial Formation (Powell, 1988).

Habitat.—Offshore in 22 to 155 m.

Subgenus PHYLLODINA?

Tellina (Phyllodina?) lebecki Anderson and Hanna, plate 3, figure 7; Plate 3; Plate 3 captions

Tellina remondii Gabb, 1864, in part, p. 156, 230, not pl. 22, fig. 132.

Tellina lebecki Anderson and Hanna, 1925, p. 154, pl. 3, fig. 10.

Original description.—“The form of this shell is not unlike T. remondii Gabb, as at first described and figured, but quite unlike that which he subsequently included under this name; the latter is here described as T. tehachapi, new species. The posterior slope in T. lebecki is straighter than in the species originally described as T. remondii from near Cochran’s, the basal margin is straighter, and the anterior end is longer; the beak of the new species is nearly in the center of the valve; no radial sculpture visible. This last characteristic constitutes one of the most distinguishing features, and differentiates it from both forms described by Gabb. In T. remondi, as described and in specimens at the University of California from the type locality, the radial sculpture is clearly shown, as it is also in the figure later published by Gabb, but which is another species.”

Holotype.—CAS 800.

Type locality.—CAS 244. In east bank of Live Oak Creek, 3/4 mile from mouth, 3 miles due east of mouth of Grapevine Canyon, Tejon Quad., Kern Co., Calif. Tejon Formation.

Geographic range.—Southern California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: Tejon Formation (Anderson and Hanna, 1925).

Tellina (Phyllodina?) englishi Clark, plate 3, figures 8a, b; Plate 3; Plate 3 captions

Tellina englishi Clark, 1915, p. 472-473, pl. 61, figs. 6, 7.

Original description.—“Shell elongate-subovate, compressed, inequilateral, rostrate posteriorly. Beaks inconspicuous, posterior to the center with a narrow, deep lunule. Right valve flatter than left and flexed near the posterior end. Anterior end evenly rounded, anterior dorsal edge straight, and nearly parallel with the ventral edge; posterior dorsal edge straight, sloping more steeply from the beak than anterior dorsal edge; ventral edge long, very gently arcuate except at point of flexure, where it is slightly incurved. Posterior to the flexure on the surface there is a prominent raised ridge which extends obliquely from the beak to the posterior extremity and parallel to the posterior dorsal edge; beyond this ridge and parallel with it, is a well-defined groove. Left valve sculptured by finer concentric lines than right valve, and corresponding to the posterior ridge seen on the right valve there is a groove situated very close to and parallel with the posterior dorsal edge; there is no well-defined line in front of this groove.”

Holotype.—UCMP 11533.

Type locality.—UC 481. NE 1/4 sec. 28, T 1 S, R 1 E, Contra Costa Co., Calif. San Pablo Formation, Miocene.

Comparison.—“Tellina englishi resembles closely Tellina idae Dall***The former differs from the latter in the following respects: the anterior dorsal edge is straighter and longer; the beaks are more posterior; the shell is longer in proportion to the height, and the ventral edge is less arcuate. Tellina englishi Davis***is also very close in resemblance to Tellina tenuistriata***The posterior end of the lower Miocene form is apparently more attenuate; the posterior dorsal slope is not so steep; the ventral edge is more arcuate and the shell is higher in proportion to the length.” (Clark, 1915, p. 473)

Geographic range.—Middle California.

Geologic range.—Miocene.

Occurrence in California.—Miocene: San Pablo Formation (Keen and Bentson, 1944).

Tellina (Phyllodina?) cumingii Hanley, plate 3, figure 9; Plate 3; Plate 3 captions

Tellina cumingii Hanley, 1844, p. 59. Jordan, 1936, p. 112, 144.

Tellina (Tellinella) cumingii Hanley. Lamy, 1909, v. 57, p.251.

Tellina (Tellina) cumingii Hanley. Durham, 1950, p. 88, pl. 23, figs. 11, 17.

Original description.—

Geologic range.—Pliocene to Holocene.

Occurrence in Baja California Sur.—Pliocene: Marquer Formation (Durham, 1950).

Subgenus TELLINELLA Mörch, 1853

“Shell elongate, subequivalve. Posterior end twisted, with one or two radial ribs. Sculpture of commarginal ribs, usually stronger in right valve. Lunule and escutcheon deep. Lateral teeth strong. Pallial sinus deep.” (Coan, Scott, and Bernard, 2000, p. 404)

Tellina (Tellinella) tenuilineata Clark, plate 4, figure 1; Plate 4; Plate 4 captions

Tellina tenuilineata Clark, 1918, p. 153, pl. 10, figs. 1 3, 5; 1929, pl. 16, fig. 1.

Tellina (Tellinella) tenuilineata Clark. Addicott, 1973, p. 32, pl. 5, figs. 2, 8.

Original description.—“Shell subovate in outline, inequivalve; rostrate posteriorly with the posterior end subtruncate; beaks nearly straight; valves slightly flexed to the right near the posterior end; left valve slightly more convex than right; anterior end regularly rounded; ventral edge regularly convex except near the posterior end, where it is slightly concave due to the flexure of the valves. Escutcheon well-defined, elongate narrow and strongly depressed, wider on the left valve, the wider part being near the middle of the posterior dorsal margin. Ligamental groove deep, shorter than the escutcheon. Lunule small and deeply inset. Surface of right valve covered by fairly fine, regularly spaced, sharp, concentric raised lines, which are closely crowded together near the beaks, the interspaces becoming wider and more regular toward the ventral edge; on the depressed posterior margin these lines are rather strongly imbricated. A fairly broad, shallow flexure sinus near the posterior dorsal edge, posterior to which the dorsal margin is depressed, the depressed area being separated from the main surface of the shell by a distinct ridge; on the depressed area, posterior to this ridge and extending from near the beak to the posterior end, is a fairly deep sinus. Left valve covered by concentric lines, which are somewhat finer and closer together than on right valve; posterior dorsal margin not so strongly depressed as on right valve. On the depressed margin there is a shallow sinus, which is not separated by a distinct ridge from the surface anterior to it.”

Holotype.—UCMP 11130.

Type locality.—UC 1175. 3/8 mile east of west end of Briones Valley on north side, Long. 122°12’46”, Lat. 37°55’51”, Contra Costa County, Calif. San Lorenzo Formation.

Comparison.—“T. tenuilineata resembles rather closely T. idea [idae] Dall, a Recent West Coast species; the two are somewhat different in outline; the beaks of the latter are more conspicuous; the raised concentric lines are somewhat coarser and on the posterior margin they appear to be more strongly imbricated. T. tenulineata lacks the fine radiating lines seen on T. idea [idae].” (Clark, 1918, p. 153-154)

Geographic range.—Middle California.

Geologic range.—Eocene to Miocene.

Occurrence in California.—Eocene and Oligocene: San Juan Batista (Allen, 1945) and San Lorenzo (Clark, 1918) Formations; Oligocene: Wygal Sandstone Member, Temblor Formation (Addicott, 1973); Miocene(?): San Ramon Formation (Clark, 1918).

Tellina (Tellinella) idae Dall, plate 4, figure 2; Plate 4; Plate 4 captions

Tellina idae Dall, 1891, p. 183, pl. 6, fig. 3; pl. 7, figs. 1, 4. Dall, 1900, p. 301, pl. 4, figs. 10, 11. I.S. Oldroyd, 1924, p. 164, pl. 14, fig. 4. Grant and Gale, 1931, p. 358, pl. 20, figs. 12, 14a, 14b.

Tellina (Angulus) idae Dall. Arnold, 1903, p. 158-159, pl. 15, fig. 6 not fig. 7.

Tellina (Tellinella) idae Dall. Hertlein and Grant, 1972, p. 285-286, pl. 53, figs. 6, 11. Coan, Scott, and Bernard, 2000, p. 404, pl. 84.

Original description.—“Shell ovate-triangular, moderately elongate, white, compressed; exterior of the right valve slightly flatter, and with more prominent sculpture than the left valve; beaks small, pointed prominent, laterally compressed, adjacent to each other; anterior part of the shell slightly longer than the part posterior to the beaks, even and regularly oval, the dorsal and basal curves almost identical; posterior dorsal slope steeper, rectilinear, obliquely truncate at its termination, but basal curve (behind the perpendicular from the beaks) similar to its anterior part as far as the flexure, which is narrow but well marked, its basal end moderately incurved; behind it rises to a strong ridge the end of which forms a rostral projection, behind which, in the right valve, is a deeply impressed line a little in advance of the posterior dorsal margin, which is strongly compressed; on the left valve there are two lines with a narrow impressed area between them, above which the dorsal margin is swollen; in front of the beaks is a narrow, acute, deeply excavated, short lunule; behind the beaks is a large, narrow, still more excavated escutcheon, most of which is excavated from the left valve, which falls short of the right valve a little; the ligament is sunken in and about half as long as the escutcheon; it is quite invisible on a lateral view of the shell; the left valve is regularly, sharply, closely, concentrically grooved, and both are obsoletely, finely, radiately striate; the margin between the impressed area of the left valve and the escutcheon is more finely grooved than the rest and has a (somewhat irregularly) denticulate dorsal edge; the right valve has the concentric sculpture more distant and ventrally, shows distinctly elevated narrow lines with wider interspaces regularly disposed, and also bears denticulations on its posterior dorsal margin; the umbones are nearly smooth, the shell gapes but little, chiefly at the end of the rostrum; internally the surface of the valves is smooth, the muscular and pallial impressions are brilliantly polished; besides the usual marks, in the specimen under examination there are, near the posterior ventral angle of the pallial sinus, two small circular impressions and some obscure and irregular markings at the entrance of the sinus, all due, doubtless, to attachments of the mantle and probably inconstant or variable in different individuals; the interior part of the pallial sinus nearly reaches the scar of the anterior adductor, and nearly the whole of the basal part is coincident with the line of the basal attachment of the mantle; the hinge plate is broad and subtriangular quite strong, bearing one prominent grooved tooth between two channels; behind the posterior channel, in the left valve, is a much narrower, obscure, and little-raised tooth; the corresponding second tooth in the right valve is anterior and similarly obscure; the left valve is destitute of lateral teeth, but in the right valve there is a short, strong, elevated, subtriangular, anterior lateral close to the anterior cardinal, and a more distant and feeble posterior lateral over the posterior adductor scar.”

Holotype.—USNM 120098.

Type locality.—“Habitat: Long Beach, San Pedro, California.”

Supplementary description.—“Shell subelliptical, longer posteriorly, thin, compressed, posterior end pointed, twisted, with two strong radial ribs. Sculpture of regular, sharp lamellar, commarginal ribs.” (Coan, Scott, and Bernard, 2000, p. 404)

“The shell of this species [Tellina idae] is characterized by the strongly rostrate posterior end and the well-developed, raised, sharp, concentric sculpture. These concentric threads are spaced a little less than 1 mm apart on the medial portion of an adult right valve.***young specimens of this species are equilateral and triangular in shape with coarser sculpture than on adults.” (Hertlein and Grant, 1972, p 286)

Geographic range.—Middle California to Baja California Norte.

Geologic range.—Miocene to Holocene.

Occurrence in the Californias.—Miocene: Cierbo and Neroly Sandstones, San Pablo Group (Hall, 1960), Pancho Rico (D.L. Durham and Addicott, 1965), Temblor (Grant and Gale, 1931) and Topanga (Vedder, written commun., 1953) Formations; Miocene and Pliocene: Towsley Formation (Winterer and Durham, 1962); Pliocene: Niguel (Vedder, 1978, written commun.) and San Diego (Hertlein and Grant, 1972) Formations; Pliocene and Pleistocene: Fernando Formation (Kennedy, 1975); Pleistocene: Unnamed sediments, Bahía San Quintin, Baja California Norte (Hertlein and Grant, 1972).

Habitat.—Living from Santa Barbara to San Diego, Calif. In sand in the intertidal zone to 100 m (Coan, Scott, and Bernard, 2000, p. 404)

SUBGENUS?

Tellina (Subgenus?) perrini Dickerson, plate 4, figure 3; Plate 4; Plate 4 captions

Tellina perrini Dickerson, 1914, p. 137-138, pl. 11, fig. 8.

Original description.—“Shell long, very narrow; beaks small and located two-fifths of the shell-length from the anterior end; anterior dorsal slope straight, with gentle slope toward the rounded anterior end; the steeper posterior dorsal slope is slightly concave from beaks outward to half its length and then it becomes convex; posterior extremity very angular; basal margin narrowly arcuate; lunule and escutcheon, long and narrow. A straight line which extends from the beaks to the sharp angular posterior extremity marks a prominent umbonal slope. The space between this slope and the posterior dorsal margin is decidedly concave. Surface of shell marked by concentric lines of growth.”

Holotype.—UCMP 11716.

Type locality.—UC 784. Near Lower Lake, at old brick yard 1/4 mile east of village, NW 1/4,NE 1/4, T. 12 N., R. 7 W., Lake County, Calif. Martinez Formation.

Comparison.—“This species can be distinguished from all other West Coast Eocene forms of the genus, Tellina, by its great length and marked umbonal slope.” (Dickerson, p. 138)

Geographic range.—Northern and middle California.

Geologic range.—Paleocene and Eocene.

Occurrence in California.—Paleocene: Martinez Formation (Dickerson, 1914); Paleocene and Eocene: Santa Susana Formation (Zinsmeister, 1983).

Tellina (Subgenus?) remondii Gabb, plate 4, figure 4; Plate 4; Plate 4 captions

Tellina rémondii Gabb, 1864, p. 156, 230, pl. 22, fig. 132; 1869, p. 237 in part, not p. 182, pl. 29, fig. 71. Clark and Woodford, 1927, pl. 17, fig. 15. Stewart, 1930, p. 200-201, pl. 8, fig. 1.

Original description.—“Shell broad, thin, compressed, about a third longer than wide; anterior end broadly rounded; posterior, rostrate, narrow and truncated obliquely outwards and downwards; beaks small, central, prominent; base broadly rounded, slightly sinuous near the posterior extremity; a well-marked ridge passes from the beak to the posterior basal angle; cardinal margin convex in front, concave behind the beaks, and sloping downwards concavely towards the truncated posterior end. Surface ornamented by numerous small, regular, concentric ribs, and by smaller radiating, interstitial lines.”

Holotype.—UCMP 3145

Type locality.—Cochran’s, 6 miles east of Mt. Diablo, Mt. Diablo Quad., S 1/2, T 1 N., R. 1 E., Contra Costa County, Calif. Meganos Formation(?). (Keen and Bentson, 1944)

Geographic range.—Central California.

Geologic range.—Paleocene and Eocene.

Occurrence in California.—Paleocene and Eocene: Meganos Formation(?) (Keen and Bentson, 1944); Eocene: Tejon Formation (Arnold, 1906; Dickerson, 1916).

Tellina (Subgenus?) soledadensis M.A. Hanna, plate 4, figures 5a,b; Plate 4; Plate 4 captions

Tellina soledadensis M.A. Hanna, 1927, p. 291, pl. 42, figs. 1, 2, 5. Turner, 1938, p. 60-61, pl. 7, fig. 5. Vokes, 1939, p. 90, pl. 14, fig. 13. Weaver, 1943, p. 196-197, pl. 48, fig. 1.

Original description.—“Shell of moderate size; outline as shown in the figures; anterior rounded; anterior dorsal and posterior dorsal nearly straight, posterior sharply rounded, ventral broadly rounded; surface sculpturing consists of fairly closely set sharp concentric ridges which are much narrower than the intervening interspaces; concentric ribs cross many rounded radial ribs which are not as wide as the interspaces separating the concentric ribs; radial ribs separated only by lines of contact of two ribs and not by interspaces.”

Syntypes.—UCMP 31368, 31369.

Type locality.—UC 3975. Two miles east of La Jolla, on east side of Rose Canyon, La Jolla Quad., San Diego County, Calif. Rose Canyon Shale.

Comparison.—“This species [T. soledadensis] most closely resembles Tellina tehachapi Anderson and Hanna***The concentric ridges, however, are much closer and finer in the new species, and the radial sculpturing more distinct. In general characters the new species differs considerably from Tellina remondii Gabb. The outline is different in the first place*** the radial sculpturing is much more prominent; and the concentric ribbing is possibly finer.” (M.A. Hanna, 1927, p. 291)

“This species [T. soledadensis] may be distinguished from T. remondii Gabb in the more elongate anterior end and in the straight posterior dorsal margin in contrast to the concave line just below the umbo as in T. remondii.” (Weaver, 1943, p. 197)

Geographic range.—Southern Oregon; southern California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: Rose Canyon Shale (M.A. Hanna, 1927).

Tellina (Subgenus?) tehachapi Anderson and Hanna, plate 4, figure 6; Plate 4; Plate 4 captions

Tellina remondii Gabb, 1869, p. 182, pl. 29, fig. 71. Not T. remondii Gabb, 1864, p. 156, pl. 22, fig. 132.

Tellina tehachapi Anderson and GD. Hanna, 1925, p. 155, pl. 6, figs. 5, 6. Hanna, M.A., p. 291.

Original description.—“A careful comparison of Gabb’s figures and descriptions is enough to make it obvious that he confused two distinct species in his revised description of T. remondii Vol. II. The species first figured does not occur in Type Tejon strata but is replaced there by T. lebecki n. sp. We have been fortunate enough to obtain a large fragment of the species last figured by Gabb as T. remondii, and it is easy to discern the differences between the two. First, there is considerable difference in size, about in the proportion of 8 to 5; second, the sculpture is decidedly coarser in the larger species, nearly 3 to 1; third, the angle subtended by the dorsal anterior and posterior margins is as 130° to 110°. The radial sculpture of the larger species is scarcely visible on the other, and in fact is usually absent. We propose the above name for the new species, the second figured by Gabb under the name of T. remondii.”

Holotype.—CAS 878.

Type locality.—CAS 244. In east bank of Live Oak Creek, 3/4 mile from mouth, 3 miles due east of Grapevine Canyon, Tejon Quad., Kern County, Calif. Tejon Formation.

Geographic range.—Southern California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: Coldwater Sandstone (Rose Canyon Shale?) (M.A. Hanna, 1927); Tejon Formation (Anderson and Hanna, 1925).

Tellina (Subgenus?) insurana Hanna

Tellina tenuistriata Davis, 1913, p. 457. Not Tellina tenuistriata Deshayes, 1824, or Amphidesma tenuistriata Sowerby in Fitton, 1836.

Tellina insurana GD. Hanna, 1924, new name, p. 183.

Original description.—“The specimens collected by the writer are from the Lower Temblor on the southern San Antonio headwaters, Monterey County, Cal. They are characterized by the fine concentric lines on both valves and low beaks. The valves are rounded in front but are oblique and gaping behind; more or less rostrate.” (Davis, 1913, p. 457)

Holotype.—Missing and presumed lost.

Type locality.—Monterey County, Calif. Temblor Formation.

Geographic range.—Middle California.

Geologic range.—Oligocene and Miocene.

Occurrence in California.—Oligocene and Miocene: Temblor Formation (Davis, 1913).

Tellina (Subgenus?) wilsoni Anderson and Martin, plate 4, figure 7a,b; Plate 4; Plate 4 captions

Tellina wilsoni Anderson and Martin, 1914, p. 62, pl. 3, figs. 11a, 11b. Adegoke, 1969, p. 130.

Original description.—“Shell small, eight to ten millimeters in length, convex, moderately inflated; valves unequal, inequilateral; beaks conspicuous, with the posterior third; anterior dorsal margin long and straight, nearly parallel to the base; anterior extremity well-rounded; basal margin very slightly arcuate; posterior dorsal margin truncated, sloping sharply downward to the posterior extremity which is sharply rounded into the base; posterior end compressed, flexuous curved to the right; surface marked by very fine concentric lines of growth which are usually invisible to the unaided eye.”

Holotype.—CAS 127.

Type locality.—CAS 126. Bed of small creek near center sec. 34, T. 28 S., R. 15 E., Pozo Quad., San Luis Obispo County, Calif. (Keen and Bentson, 1944) Temblor Formation.

Geographic range.—Southern California.

Geologic range.—Oligocene and Miocene.

Occurrence in California.—Oligocene and Miocene: Temblor (Adegoke, 1969) andVaqueros (Keen and Bentson, 1944) Formations; Miocene: Round Mountain Silt (Keen, 1943) and Saltos Shale Member, Monterey Formation (Addicott and others, 1978).

Tellina (Subgenus?) praecuta Clark, plate 4, figure 9; Plate 4; Plate 4 captions

Tellina praecuta Clark, 1918, p. 153, pl. 12, fig. 13.

Original description.—“Shell elongate-ovate, strongly rostrate posteriorly; beaks inconspicuous, anterior to the middle of the shell, right valve rather strongly flexed near the posterior end. Posterior dorsal margin long and straight; anterior dorsal margin gently convex, shorter than posterior margin; anterior end regularly rounded; posterior end narrow and truncated; ventral edge long and gently arcuate except near posterior end where it is slightly concave due to the flexure of the valve. Surface sculpturing not well preserved on specimens at hand but enough is seen to show that it is of the same general type as T. tenuilineata and T. idea [idae], having the same type of depressed posterior margin.”

Holotype.—UCMP 11166.

Type locality.—UC 14. In valley north of Sobrante Ridge, on west fork of Bear Creek, 1/2 mile from source, Long 122° 12’35”, Lat. 37°55’, Concord Quad., Contra Costa County, Calif. San Ramon Sandstone.

Geographic occurrence.—Middle California.

Geologic occurrence.—Miocene?

Occurrence in California.—Miocene?: San Ramon Sandstone (Keen and Bentson, 1944).

Genus TELLINA?

Tellina? sutterensis Dickerson, plate 4, figures 8a,b; Plate 4; Plate 4 captions

Tellina sutterensis Dickerson, 1913, p. 290, pl. 14, figs. 3a, 3b. Anderson and Hanna, 1925, p. 156.

Original description.—“Shell, oblong, compressed, thin. Beaks prominent, being located about one-third of distance from the anterior end. Anterior and posterior extremities rounded; the anterior dorsal margin slopes from the beaks more steeply than the posterior dorsal margin. Surface marked by minute lines of growth.”

Holotype.—UCMP 11767.

Type locality.—UC 1853. Marysville Buttes, N 1/2, sec. 28, T. 16 N., R. 1 E., Marysville Buttes Quad., Sutter County, Calif. (Keen and bentson, 1944) Meganos Formation.

Supplementary description.—“This species [T. sutterensis] does not appear to belong to the genus Tellina, and certainly does not form a part of the Type Tejon Group.” (Anderson and Hanna, 1925, p. 157)

Geographic range.—Northern and middle California.

Geologic range.—Paleocene.

Occurrence in California.—Paleocene: Marysville Claystone Member, Meganos Formation (Keen and Bentson, 1944)

Tellina diegoana Conrad, nomen dubium

Tellina diegoana Conrad, 1855, p. 12. 1857, p. 323, pl. 3, fig. 28. Dall, 1909, p. 166.

Original description.— “Ovate-elliptical, compressed, inequilateral, concentrically striated. Slope carinated; posterior extremity suddenly produced or rostrated, and below the posterior basal margin.”

Holotype.—Missing and presumed lost.

Type locality.—“San Diego in sandstone. Miocene.”

Tellina hornii Gabb=Gari hornii (Gabb)

Tellina oregonensis Conrad, nomen dubium (Moore, 1964, p. 79).

Addicott (1973, p. 32) synonymized T. oregonensis with Tellina (Oudardia) emacerata Conrad (1848).

Tellina (Moerella) salmonea (Carpenter)=Tellina (Cadella) nuculoides (Reeve)

Genus MACOMA Leach, 1819

“Shell ovate to subtrigonal, inequilateral. Sculpture usually absent, or weakly commarginal. Periostracum thin, frequently abraded. Two cardinal teeth in each valve; lateral teeth absent. Pallial sinuses discrepant, longer in left valve.” (Coan, Scott, and Bernard, 2000, p. 408)

Geographic range.—Cosmopolitan.

Geologic range.—Eocene to Holocene.

Subgenus MACOMA

Shell ovate to trigonal, chalky, moderately inflated. (Coan, Scott, and Bernard, 2000, p. 408)

Geographic range.—Northrn Europe, North Amrica, northeast Asia.

Macoma (Macoma) brota Dall, plate 5, figure 1; Plate 5; Plate 5 captions

Tellina edentula Broderip and Sowerby, 1829, not Spengler, 1793.

Macoma brota Dall, 1916, new name, p. 413. I.S. Oldroyd, 1924, p. 170, pl. 9, fig. 2. Grant and Gale, 1931, p. 368.

Macoma (Macoma) brota Dall. Coan, Scott, and Bernard, 2000, p. 408, pl. 84.

Original description.—

Holotype.—

Type locality.—Bering Strait.

Supplementary description.—“Shell heavy, subquadrate; posterior end broadly truncate. Periostracum silky, usually abraded. Pallial sinus deep in left valve, moderate in right, substantially detached from pallial line in both valves. Length to 75 mm.” (Coan, Scott, and Bernard, 2000, p. 408)

Geographic range.—Living: Bering Sea to Puget Sound, Washington; fossil: middle California.

Geologic range.—Miocene to Holocene.

Occurrence in California.—Miocene: Pancho Rico (Durham and Addicott, 1965) Formation; Miocene and Pliocene:Tahana Member, Purisima (Cummings and others, 1962) Formation.

Macoma (Macoma) lipara Dall, plate 5, figure 2; Plate 5; Plate 5 captions

Macoma brota lipara Dall, 1916b, nomen nudum, p. 36; 1916a, p. 414. I.S. Oldroyd, 1924, p. 171, pl. 42, fig. 6.

Macoma (Macoma) lipara Dall. Coan, Scott, and Bernard, 2000, p. 410, pl. 85.

Original description.—

Holotype.—USNM 223032.

Type locality.—Bering Strait.

Supplementary description.—“Shell ovate, heavy anterior end longer, both ends rounded. Periostracum thin, silky. Pallial sinus deep in left valve, moderate in right, substantially detached in both valves. Length to 75 mm. (Coan, Scott, and Bernard, 2000, p. 410)

Comparison.—“Similar to M. (M.) brota but heavier and more ovate. (Coan, Scott, and Bernard, 2000, p. 410)

Geographic range.—Living: Alaska to southern California; fossil: Middle California.

Geologic range.—Miocene to Holocene.

Occurrence in California.—Miocene and Pliocene: Purisima Formation (Cummings and others,1962).

Macoma (Macoma) calcarea (Gmelin), plate 5, figure 3; Plate 5; Plate 5 captions

Tellina calcarea Gmelin, 1791, p. 3231.

Macoma calcarea Gmelin. Arnold, 1903, p. 161, pl. 16, fig. 2. Dall, 1909, p. 126-127, pl. 14, fig. 8. I.S. Oldroyd, 1924, p. 173, pl. 42, fig. 5.

Macoma calcarea (Gmelin). Grant and Gale, 1931, p. 369-370. Weaver, 1943, p. 212-213, pl. 49, fig. 11.

Macoma (Macoma) calcarea (Gemlin). Coan, Scott, and Bernard, 2000, p. 409, pl. 84.

Original description.—“Testa ovali tenui alba, cardinis dente primario in altera valva fisso, alterius foveae inserto.”

Holotype.—

Type locality.—

Supplementary description.—“Shell subovate, moderately inflated; posterior end produced, slightly pointed, slightly flexed to right. ***Pallial sinus very deep in left valve, moderate in right valve, substantially detached in both valves. Escutcheon lacking. Length to 60 mm.” (Coan, Scott, and Bernard, 2000, p. 409)

Geographic distribution.—Living: Panarctic and circumboreal; fossil: Washington to southern California.

Geologic distribution.—Miocene to Holocene.

Occurrence in California.—Miocene and Pliocene: San Gregorio Member, Purisima Formation (Cummings and others, 1962); Pliocene and Pleistocene: Fernando (Soper and Grant, 1932), Merced (Arnold and Hanibal, 1913), Pico (Waterfall, 1929) and Rio Dell (Faustman, 1964) Formations, San Pedro Group, Saugus (Waterfall, 1929) and Wildcat (Martin, 1916) Formations; Pleistocene: unnamed sediments southern California (Stephens, 1929).

Habitat.—“10-360 m, in mud and sand.” (Coan, Scott, and Bernard, 2000).

Macoma (Macoma) elimata Dunnill and Coan, plate 5, figure 4; Plate 5; Plate 5 captions

Macoma elimata Dunhill and Coan, 1968, p. 1, figs. 1, 2a-e, 3, 6.

Macoma (Macoma) elimata Dunnill and Coan. Hertlein and Grant, 1972, p. 291-292, pl. 53, fig. 5. Coan, Scott, and Bernard, 2000, p. 410, pl. 84.

Original description.—“The shell is moderately inflated, reaching its maximum thickness well anterior to the umbos. The umbos are fairly prominent and slightly raised above the dorsal margin. The shell is ovate anteriorly; posteriorly the dorsal margin is straight and steeply sloping. The anterior end is truncate. The periostracum is greenish grey and flaky and is little eroded except around the umbos. The shell is chalky white and is covered with fine, concentric growth lines. The posterior dorsal margin has a flattened, concave escutcheon. The valves are flexed toward the right posteriorly.

“***The pallial sinuses are discrepant, long in the left valve (stopping just short of the adductor scar), much shorter and lower in the right valve. Both pallial sinuses loop back along the pallial line and are confluent with it beneath the umbos. The posterior cruciform muscle scar occurs near the ventral-posterior tip of the pallial line and divides into two parts, with a small anterior element. The anterior cruciform scar lies immediately ventral to the pallial line. There are two cardinal teeth in each valve. The left anterior and right posterior teeth are projecting and bifid, while the right anterior and left posterior teeth are projecting, lamellar, and fragile. The left posterior tooth is the thinnest and frequently breaks off when the valves are opened. The holotype is 27.2 mm long, 20.7 mm high, and 9.6 mm thick (both valves).”

Holotype.—National Museum of Canada, Division of Mollusks 46070.

Type locality.—Moresby Island, Satellite Channel, Vancouver Island, British Columbia. Holocene.

Supplementary description.—“Shell subovate; anterior end much longer, rounder; posterior end produced, truncate terminally; ligament sunken in deeply beveled escutcheon.” (Coan, Scott, and Bernard, 2000)

Geographic range.—Living: Aleutian Islands to southern California; Fossil: Southern California to Baja California Norte.

Geologic range.—Pliocene to Holocene.

Occurrence in the Californias.—Pliocene: San Diego Formation (Hertlein and Grant, 1972); Pliocene or Pleistocene: Unnamed sediments at Bahía San Quentin (Grant and Gale, 1931; Pleistocene: Palos Verdes Sand (DeLong, 1941).

Habitat.—”9-435 m, in sand and silt.” (Coan, Scott, and Bernard, 2000)

Subgenus MACOMA?

Macoma (Macoma?) sheridani Vokes, plate 5, figure 5; Plate 5; Plate 5 captions

Macoma sheridani Vokes, 1939, p. 92, pl. 14, figs. 21, 22.

Original description.—“Shell small, thin, moderately inflated, subovate; umbos small, posterior; anterior dorsal margin slightly convex, the anterior margin broadly rounded, the ventral margin convex, the posterior margin sharply rounded; posterior dorsal margin straight; umbonal angle 138 degrees; posterior curved to right; both valves with a slight umbonal ridge to the posterior ventral edge, bordered on either side by a broad shallow fold; surface sculptured only by fine, regular, concentric lines of growth.”

Holotype.—UCMP 15703.

Type locality.—UC A-1154. San Benito County, Calif.

Comparison.—“Macoma sheridani differs from M. rosa Hanna***in lacking a sculpture of concentric ridges, in having a shorter posterior dorsal slope and a less sharply rounded posterior end, and in lacking a posterior ventral lobation. M. viticola Anderson & Hanna***is smaller and differs greatly in outline.” (Vokes, p. 92)

Geographic range.— Middle California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: Domengine Formation (Vokes, 1939).

Macoma (Macoma?) menkeni GD. Hanna and Hertlein, plate 5, figure 7; Plate 5; Plate 5 captions

Macoma menkeni GD. Hanna and Hertlein, 1938, p. 106, pl. 21, figs. 1, 2.

Original description.—“Shell subcircular; slightly projecting posteriorly with an angulation running from the beak to the ventral margin, the posterior margin of the shell sloping rapidly downward, and a broad gentle depression anterior to the fold causing a slanting bend in the lines of growth; beaks about two-fifths the distance from the anterior end. Length, 41 mm.; height (beak to base), 34 mm.”

Holotype.—CAS 6900.

Type locality.—CAS 28,682. Chancellor Canfield Midway Oil Co., well no 7, sec. 6,T. 28 S., R. 29 E., Mount Diablo Base and Meridian, Kern County, Calif., at a depth of 1,223 to 1, 240 feet. Temblor Formation.

Comparison.—“Macoma menkeni has a much more rounded outline, and the beaks are more anteriorly placed than in the Recent M. secta (Conrad).***The same characters separate it from M. panzana Wiedey*** described from the Miocene and M. inquinata affinis Nomland***from the Pliocene.” (GD. Hanna and Hertlein, 1938)

Geographic range.—Southern California.

Geologic range.—Oligocene and Miocene.

Occurrence in California.—Oligocene and Miocene: Temblor Formation (GD. Hanna and Hertlein, 1938)

Macoma (Macoma?) nasuta (Conrad), plate 5, figure 8; Plate 5; Plate 5 captions

T[ellina]. nasuta Conrad, 1837, p. 258.

Not Tellina nasuta Conrad, 1849=Tellina subnasuta Conrad, 1865.

Macoma nasuta (Conrad). Gabb, 1869, p. 93. Arnold, 1903, p. 163, pl. 16, fig. 3. Clark, 1915, pl. 61, fig. 16. Packard, 1918, p. 279, pl. 23, figs. 1a-d. Loel and Corey, 1932, p. 228, pl. 43, figs. 7, 8.

Macoma (Macoma) nasuta Conrad. Hertlein and Grant, 1972, p. 293-294, pl. 53, fig. 10; pl. 54, fig. 6.

Macoma (Macoma?) nasuta Conrad. Coan, Scott, and Bernard, 2000, p. 420, pl. 87.

Original description.—“Shell ovate, compressed, smooth but not polished; anterior side dilated; posterior side cueiform, extremity truncated, much above the line of the base; fold carinated on the superior valve; beaks central, slightly prominent; epidermis extremely thin and deciduous, finely wrinkled, brown; palleal[pallial] impression of the left valve joining the anterior cicatrix at its lower posterior angle. Length, an inch and three quarters. Height an inch and a third.”

Syntype.—BM(NH) 1861.5.21.158.

Type locality.—San Diego, Calif.

Supplementary description.—It [M. nasuta] is characterized by the nearly centrally placed beaks and bent, obliquely pointed, posterior end. The pallial sinus in the right valve extends to the anterior adductor impression but in the left valve it extends anteriorly, then slopes to and coalesces with the pallial line at about two-thirds the length of the shell. This varies, and in occasional specimens the sinus slopes slightly posteriorly before joining the pallial line.” (Hertlein and Grant, 1972, p. 293)

“Shell narrowly subovate, subequilateral; posterior end produced. Pallial sinus in left valve extremely deep, merging with anterior adductor scar; deep, not detached in right. Length to 110 mm, usually less than 75 mm.” (Coan, Scott, and Bernard, 2000, p. 420.)

Comparison.—“This species [Macoma nasuta] is homologous and very similar to the Japanese M. tokyoensis Makiyama***which differs in having a more beveled escutcheon, a more regular outline, and a pallial sinus in the left valve that does not reach the anterior aductor muscle scar.” (Coan, Scott, and Bernard, 2000, p. 420)

Geographic range.—Living: Alaska to Baja California Sur; fossil: Middle to southern California.

Geologic range.—Oligocene to Holocene.

Occurrence in California.—Oligocene and Miocene: Vaqueros Formation (Loel and Corey, 1932); Miocene: San Pablo Group (Clark, 1915); Miocene and Pliocene: Etchegoin Formation (Arnold, 1910); Pliocene: Careaga Sandstone (Arnold, 1907); Pliocene and Pleistocene: San Pedro Formation (Arnold, 1903).

Habitat.—According to Fitch (1953, p. 74) “this clam [Macoma nasuta] always lies on the left side and its siphons are extended to the surface for feeding and are freely withdrawn and re-extended to a different spot.” He also says that it is “mostly found in heavy mud or muddy sand of sheltered bays, lagoons and estuaries at depths of 4 to 8 inches [10 to 20 mm] beneath the mud.”

“***in the intertidal zone to 50 m, in exposed to sheltered situations, usually in sand or silt.” (Coan, Scott, and Bernard, 2000, p. 420)

Macoma (Macoma?) inquinata inquinata (Deshayes), plate 5, figure 6; Plate 5; Plate 5 captions

Tellina inquinata Deshayes, 1855, p. 357.

Macoma inquinata (Deshayes). Carpenter, 1864, p. 689. Grant and Gale, 1931, p. 367, pl. 20, fig. 5. Arnold, 1903, p. 162, pl. 16, fig. 4. Arnold, 1910, p. 164, pl. 24, fig. 3. I.S. Oldroyd, 1924, p. 172, pl. 45, figs. 2a, 2b, 3a,3b.

Macoma (Macoma) inquinata Deshayes. Hertlein and Grant, 1972, p. 292-293, pl. 52, figs. 1, 10.

Macoma (Macoma?) inquinata (Deshayes). Coan, Scott, and Bernard, 2000, p. 419, pl.87.

Macoma inquinata arnheimi Dall, 1916, p. 414.

Original description.—“T. testa trigona, crassa, solida, depressiuscula, inaequilaterali, sub epidermide squalide fusca albofusca, ferrugineo inquinata, transversim irregulariter striata, intus candida; latere antico late obtuso, sumsemicirculari, superne parum declivi; latere postico cuneiformi, attenuato, superrne recto et declivi, extremitate oblique truncato, inferne oblique angulato, flexura parum perspicua; ligamento praelongo, incrassato; cardine bidentato, dentibus lateralibus nullis; sinu pallii magno, profundo, superne gibboso, deinde declivi et apice acuto”

Holotype.—BM(NH).

Type locality.—From the Columbia River?, Oregon.

Suplementary description.—“Shell subovate, moderately inflated; posterior end longer, produced. Pallial sinuses in both valves very deep, not detached. Length to 55 mm.” (Coan, Scott, and Bernard, 2000, p. 419)

Comparison.—“Macoma contabulata (Deshayes)***is more rounded ventrally.” (Coan, Scott, and Bernard, 2000, p. 419)

Geographic range.—Living: Bering Strait to Santa Barbara, Calif.; fossil: Middle to southern California.

Geologic range.—Miocene to Holocene.

Occurrence in California.—Miocene: Santa Margarita Formation (Addicott and others, 1978); Miocene and Pliocene: Etchegoin (Arnold and Anderson, (1907) and Purisima (Martin, 1916) Formations; Pliocene: Ohlson Ranch (Peck, 1960), San Diego (Hertlein and Grant, 1972), and San Joaquin (Adegoke, 1969) Formations; Pliocene and Pleistocene: Merced (Martin, 1916) and Rio Dell (Faustamn, 1964) Formations; Pleistocene: Timms Point Silt Member, San Pedro Formation (A. Clark, 1931).

Habitat.—Intertidal zone to 50 m, in bays and offshore in silt. (Coan, Scott, and Bernard, 2000)

Macoma (Macoma?) inquinata affinis Nomland, plate 5, figure 9; Plate 5; Plate 5 captions

Macoma inquinata affinis Nomalnd, 1917a, p. 233, pl. 9, figs. 1, 1a-b.

Macoma inquinata (Deshayes) var. affinis Nomland. Grant and Gale, 1931, p.368.

Original description.—“Shell large, equivalve, short, trapezoidal, with rather long ligamental groove. Sides moderately convex, slightly excavated a little below anterior dorsal margin, giving a flange-like appearance, with depressed area on both valves extending from umbones to posterior dorsal margin. Beaks low, adjacent, a little anterior to middle. Anterior margin evenly rounded, with increased convexity at anterior extremity; posterior dorsal margin arcuate, with greater curvature behind ligamental groove; posterior ventral margin concave where intersected by depression extending from beak, on most specimens base more strongly curved a little posterior to middle. Surface covered by numerous, unequal concentric lines. Dimensions: height, 52 mm.; length, 63 mm.”

Holotype.—UCMP 11092.

Type locality.—UC 2965. SE cor. NE 1/4, sec. 36, T.22 S., R. 16 E. Immediately north of road [Garza Creek, Kings County] Mya japonica zone, uppermost Etchegoin.

Comparison.—“This species [M. inquinata affinis] may be distinguished from the typical Macoma inquinata (Deshayes) by its larger size, the flange immediately anterior to the beaks, depressed area extending from umbones to posterior ventral margin, rather long ligamental groove, and increased convexity near middle of base.” (Nomland, 1917a, p. 233)

Geographic range.—Middle to southern California.

Geologic range.—Miocene and Pliocene.

Occurrence in California.—Miocene: Pancho Rico Formation (Durham, 1966); Pliocene: uppermost Etchegoin (Nomland, 1917a) and San Joaquin (Adegoke, 1969) Formations.

Macoma (Macoma?) affinis plena Stewart, plate 5, figure 10; Plate 5; Plate 5 captions

Macoma affinis plena Stewart in Woodring, Stewart, and Richards, 1940, p.93, pl. 29, fig. 12; pl. 39, fig. 3.

Macoma affinis Nomland plena Stewart. Adegoke, 1969, p. 130, pl. 6, fig. 4.

Original description.—“This form is about half as long as M. affinis; it also is more circular, and some specimens are more inflated. The pallial sinus is not well known.”

Holotype.—USNM 495853.

Type locality.—USGS loc. 12841. Between fork of Arreyo Robador, north of El Campo, north dome of Kettleman Hills, 2530 ft. south, 1430 ft west of NE cor. sec. 22, T. 22 S., R. 18 E., Kings County, Calif. Etchegoin Formation, Kettleman Hills, California.

Geographic range.—Southern California.

Geologic range.—Miocene and Pliocene.

Occurrence in California.—Miocene and Pliocene: Etchegoin Formation (Stewart, 1940; Adegoke, 1969); Pliocene: San Joaquin Formation (Adegoke, 1969).

Subgenus PSAMMACOMA Dall, 1900

“Shell elongate, thin, inflated.***Escutcheon and lunule absent. Pallial sinus short, slightly larger in left valve.” (Coan, Scott, and Bernard, 2000, p. 413)

Geographic range.—Northeastern Pacific, eastern North America, East Indies.

Geologic range.—Miocene to Holocene.

Macoma (Psammacoma) siliqua (C.B. Adams), plate 6, figure 1; Plate 6; Plate 6 captions

Macoma (Psammacoma) siliqua C.B. Adams. Powell, 1988, p. 16.

Macoma (Psammacoma) siliqua siliqua (C.B. Adams). Keen, 1974, p. 229, fig. 566.

Type locality.—Panama.

Occurrence in California.—Miocene and Pliocene: Imperial Formation (Powell, 1988).

Macoma (Psammacoma) yoldiformis Carpenter, plate 6, figure 2; Plate 6; Plate 6 captions

Macoma yoldiformis Carpenter, 1864, p. 639. Arnold, 1903, p. 165, pl. 16, fig. 6. Packard, 1918, p. 280, pl. 25, fig. 6. Grant and Gale, 1931, p. 373. Palmer, 1958, p. 108-109, pl. 13, figs. 2-4. I.S. Oldroyd, 1924, p. 177, pl. 44, fig. 6.

Macoma (Psammacoma) yoldiformis Carpenter. Coan, Scott, and Bernard, 2000, p. 414, pl. 86.

Original description.—

Neotype.—USNM 4507 (Palmer, 1958, pl. 14, figs. 3, 4.

Type locality.—Neah Bay, Wash.

Supplementary description.—“Shell small, subelliptical, compressed, very thin and fragile; umbones slightly posterior to center; anterior end evenly rounded, longer than posterior side, which is very faintly folded, biangular and more cuneiform; surface smooth, except for very fine incremental lines; ligamental area scooped out about one-half length of posterior end; teeth very small.” (Arnold, 1903, p. 165)

“Shell subelliptical, longer posteriorly, thin, inflated; posterodorsal margin produced into flange. Periostracum shiny, thin, adherent. Pallial sinuses moderate in both valves; substantially detached in left valve, moderately in right. Length to 25 mm.” (Coan, Scott, and Bernard, 2000, p. 414)

Geographic range.—Living: Alaska to Baja California Sur; fossil: Northern California to Baja California Norte.

Geologic range.—Miocene to Holocene.

Occurrence in the Californias.—Miocene and Pliocene: Towsely Formation (Kern, 1973); Pliocene and Pleistocene: Fernando (Kennedy, 1975), Rio Dell (Faustman, 1964), San Pedro (Arnold, 1903), Saugus (Waterfall, 1929), and Wildcat (Martin, 1916) Formations; Pleistocene: Unnamed strata in southern California and Baja California Norte.

Habitat.—“Intertidal zone to 100 m, in bays and protected foreshores in sand or mud.” (Coan, Scott, and Bernard, 2000, p. 414)

Macoma (Psammacoma) acolasta Dall, plate 6, figure 3; Plate 6; Plate 6 captions

Macoma acolasta Dall, 1921, p. 21. Dall, 1925, p. 19, pl. 8, figs. 21, 3.

Macoma (Macoma) acolasta Dall. Hertlein and Grant, 1972, p. 290-292, pl. 53, figs. 12, 13.

Macoma (Psammacoma) acolasta Dall. Coan, Scott, and Bernard, 2000, p.474, pl. 86.

Original description.—“Shell small, inequilateral, inequivalve, posterior end somewhat bent to the right, surface smooth except for faint incremental lines which are stronger on the posterior area; beaks not prominent, nearer the posterior end; both dorsal slopes somewhat arched, anterior end evenly rounded, base slightly arcuate, posterior end very slightly rostrate; left valve more convex; hinge feeble, right valve with two small cardinals, left valve with a single bifid tooth; pallial sinus in the left valve, subovate, reaching a little beyond the middle of the valve, the lower two-thirds coalescent with the pallial line; in the right valve the sinus is almost triangular.”

Holotype.—USNM 333113.

Type locality.—Bahía San Quintin, Baja California Norte.

Supplementary description.—“Shell elliptical, thin, anterior end longer, posterior end rounded.***Pallial sinuses in both valves moderately shallow, moderately detached. Length to 30 mm.” (Coan, Scott, and Bernard, 2000, p. 414)

Geographic range.—Living: Middle to southern California; fossil: Southern California to Baja California Norte.

Geologic range.—Pliocene to Holocene.

Occurrence in the Californias.—Pliocene: San Diego Formation (Hertlein, 1972); Pleistocene: Unnamed sediments in southern California and Baja California Norte.

Habitat.—Living from Bodega Bay to San Pedro, California. In the intertidal zone to 75 m, in sand of exposed areas. (Coan, Scott, and Bernard, 2000)

Subgenus PSAMMACOMA?

Macoma (Psammacoma?) arctata (Conrad), plate 6, figure 4; Plate 6; Plate 6 captions

Tellina arctata Conrad, 1849, p. 725, atlas pl. 18, figs. 3, 3a. Conrad, 1865, p. 152. Reagan, 1909, p. 184, 186, pl. 2, figs. 16, 16a.

Tellina arctata Conrad var. juana Reagan, 1909, p. 186, pl. 1, fig. 17.

Macoma arctata (Conrad). Dall, 1909, p. 126. Clark, 1929, pl. 22, figs. 2, 4. Weaver, 1943, p. 208-209, pl. 49, figs. 3, 5, 12; pl. 59, fig. 15. Hall, 1958, p. 55, pl. 8, fig. 4. Moore, 1964, p. 81, pl. 28, figs. 6, 7, 10, 11, 13; pl. 29, fig. 8. Addicott, 1972, pl. 1, fig. 14. Addicott, 1973, p. 33, pl. 5, figs. 4, 7.

Macoma wynootcheenis Weaver, 1912 [in part], p. 66, pl. 15, fig. 130 [not figs. 128, 129].

Macoma arctata (Conrad) var. wynootcheensis Weaver. Weaver, 1942, p. 209, pl. 49, fig. 8.

Original description.—“Oblong subeliptical, compressed; front very obliquely truncate and a little sinuous, below reflected; basal margin arcuate; ligament margin declining, arcuate; posterior extremity rounded. Beak nearest the anterior extremity.”

Holotype.—USNM 3489.

Type locality.—Astoria, Oregon.

Supplementary description.—“This species is characterized by moderately large, elongated valves that have posteriorly situated beaks and a fairly strong posterior flexure.” (Addicott, 1973, p. 33)

Comparison.—”It [Macoma arctata] is somewhat similar to the living species, Macoma nasuta (Conrad), which has a higher shell and more centrally located beaks and which is more acute and more strongly flexed posteriorly.” (Addicott, 1973, p. 33)

Geographic range.—Gulf of Alaska to southern California.

Geologic range.—Oligocene to Miocene.

Occurrence in California.—Oligocene: Phacoides and Wygal Sandstone Member, Temblor Formation (Addicott, 1973); Miocene: Gould Shale Member, Monterey Formation (Addicott and others,1978).

Genus REXITHAERUS Tryon, 1869

“Shell compressed to moderately inflated, thin. Equivalve to inequivalve. Posterior end flexed to right, set off by radial fold in most.” (Coan, Scott, and Bernard, 2000, p. 415)

Geographic range.—Western North America.

Geologic range.—Eocene?; Oligocene to Holocene.

Macoma (Rexithaerus) copelandi Wiedey, plate 6, figure 5; Plate 6; Plate 6 captions

Macoma copelandi Wiedey, 1928, p. 149-150, pl. 19, fig. 2.

Original description.—“Shell of small size, subovate in outline, distinctly inequivalve, very inequilateral, and quite inflated. Anterior dorsal margin long, sloping at a very low angle from the beaks and gently convex in contour. The anterior dorsal extremity is regularly but more sharply rounded. The basal margin is gently rounded. Posterior dorsal extremity sharply truncated and twisted with the posterior dorsal margin nearly straight, but sloping away quite sharply from the beaks. Umbones elevated, prominent, and sharp, more markedly on the right than on the left valve; beaks prominent, elevated slightly, adjacent, inturned, and sharp. A faint fold passes from the beak on the right valve to the posterior dorsal extremity, in front of which there is a distinct depression. The posterior end of the shell is turned to the right and is more apparent on the right than on the left valve, since the left valve is broadly convex and shows no folding. Strong concentric incremental lines of growth are the only visible sculpture. Length, 30 mm.; breadth, 20 mm.; thickness of the attached valves, 10 mm.”

Holotype.—SDNM 37.

Type locality.—SDNM 432. Two miles west of Simmler, San Luis Obispo County Calif. Temblor Formation.

Comparison.—M. copelandi “is differentiated from its resemblant form, M. indentata Carpenter, var. tenuirostris Dall, in being longer, more inflated anteriorly, and in lacking the prominent shoulder found in the posterior portion of the varietal form. It is resembled in some respects by M. andersoni Clark, but is more elongate and much more inequilateral.” (Wiedey, 1928, p. 149)

Geographic range.—Southern California.

Geologic range.—Oligocene and Miocene.

Occurrence in California.—Oligocene and Miocene: Temblor Formation (Wiedey, 1928; Adegoke, 1969); Miocene: Gould Shale Member, Monterey Group (Addicott, 1972, 1969), Round Mountain Silt (Keen, 1943).

Macoma (Rexithaerus) panzana Wiedey, plate 6, figure 6; Plate 6; Plate 6 captions

Macoma panzana Wiedey, 1928, p. 150-151, pl. 19, fig. 1.

Macoma secta (Conrad) panzana Wiedey. Loel and Corey, 1932, p. 228, pl. 43, fig. 5.

Original description.—“Shell of this species large, of subcircular outline, slightly inequilateral, thin shelled, and well inflated. Anterior dorsal margin gently convexly rounded, sloping quite sharply downward from the beak to the extremity, where it is very broadly rounded. The basal margin is broadly convex to the posterior dorsal extremity, which is truncated. The posterior dorsal margin slopes nearly straight down from the beak to the extremity. Umbo rather large, inflated, prominently rounded, and broad; beak small, slightly elevated, inconspicuous, and situated slightly posterior to the middle of the valve. A moderately sharp fold, in front of which, on the main body of the shell, there is a slightly depressed area, extends from the beak to the posterior dorsal extremity. Concentric incremental lines of growth form the only sculpturing. Length, 60 mm.: breadth, 53 mm.; thickness of the single valve, 11 mm.”

Holotype.—SDNM 38.

Type locality.—SDNM 432. East slope of the first ridge west of Syncline Hill, two miles west of Simmler, San Luis Obispo County, Calif. Temblor Formation.

Comparison.—“This new species [M. panzana] is more broadly rounded in outline than M. secta Conrad and lacks the large area posterior to the beaks found in that species.” (Wiedey, 1928, p. 151)

Geographic range.—Southern California.

Geologic range.—Oligocene to Miocene.

Occurrence in California.—Oligocene and Miocene: Temblor (Wiedey, 1928; Adegoke, 1969) and Vaqueros (Loel and Corey, 1932) Formations.

Macoma (Rexithaerus) indentata indentata Carpenter, plate 6, figure 7; Plate 6; Plate 6 captions

Macoma indentata Carpenter, 1864, p. 611. Arnold, 1903, p. 161, pl. 16, fig. 1. Packard, 1918, p. 277, pl. 25, fig. 4.

Macoma (Rexithaerus) indentata Carpenter. Palmer, 1958, p.109, pl. 16, figs. 1, 2. Coan, Scott, and Bernard, 2000, p. 415, pl. 87.

Original description.—“Like secta, jun., but beaked, indented and ventrally produced.”

Holotype.—USNM 15229.

Type locality.—San Pedro, Calif.

Supplementary description.—“Shell narrowly subovate; posterior end longer, acute, pointed, set off by pronounced flexure; posteriodorsal margin prolonged into flange. Pallial sinuses in both valves moderate, slightly detached. Length to 100 mm.” (Coan, Scott, and Bernard, 2000, p. 415)

Comparison.—“This species is more ovate and pointed posteriorly than M. (R.) secta. (Coan, Scott, and Bernard, 2000, p. 415.

“The subspecies Macoma indentata tenuirostris Dall is decidedly more elongated than the typical form.” M. vanvlecki differs “in the much longer and much more convex form.

“Macoma moliniana Dall ***has a strong posterior flexure but the shape of the pallial sinus is quite different from that on the corresponding valve of M. indentata.” (Hertlein and Grant, 1972, p. 296)

Geographic range.—Living: Humboldt Co., Calif., to Isla Santa Margarita, Baja California Sur, and Golfo de California to Guaymas, Sonora, Mexico; fossil: Middle California to Baja California Norte.

Geologic range.—Miocene to Holocene.

Occurrence in California.—Miocene: Pancho Rico (Durham and Addicott, 1965), and Santa Margarita (Nomland, 1917; Addicott and others, 1978) Formations; Miocene and Pliocene: Etchegoin (Martin, 1916; Adegoke, 1969) and Towsley (Kern, 1973) Formations; Pliocene and Pleistocene: Fernando (Arnold, 1907) and San Pedro (Arnold, 1903) Formations; Pleistocene: Unnamed strata, Baja California Norte.

Habitat.—“15 to 46 m, in sandy mud or in sand.” (Hertlein and Grant, 1972, p. 296) “Intertidal zone to 100 m, in silt and sand of bays and protected foreshores.” (Coan, Scott, and Bernard, 2000, p. 415)

Macoma (Rexithaerus) indentata tenuirostris Dall

Macoma (Rexithaerus) indentata var. tenuirostris Dall, 1900, p. 324.

Macoma (Rexithaaerus) indentata tenuirostris Dall. Hertlein and Grant, 1972, p. 297, pl. 41, fig. 15; pl. 50, fig. 7; pl. 52, fig. 2.

Original description.—“This form differs from the typical indentata in being more elongated, with a shorter and more pointed posterior end and deeper flexure.”

Holotype.—USNM 73469.

Type locality.—San Pedro, Calif.

Comparison.—Hertlein and Grant (1972, p. 297) considered M. indentata tenuirostris to differ from M. indentata in the characters cited by Dall. Coan, Scott, and Bernard (2000, p. 415) considered it to be conspecific.

Geographic range.—Living: Southern California to Baja California Norte; fossil: Southern California.

Geologic range.—Pliocene to Holocene.

Occurrence in California.—Pliocene: San Diego Formation (Hertlein and Grant, 1972).

Macoma (Rexithaerus) secta (Conrad), plate 6, figure 8; Plate 6; Plate 6 captions

Tellina secta Conrad, 1837, p. 257.

Macoma secta Conrad. H. and A. Adams, 1858, p. 401. Arnold, 1903, p. 164, pl. 16, fig. 5. Packard, 1918, p. 280, pl. 25, fig. 8. Grant and Gale, 1931, p. 374, pl. 20, figs. 6a, 6b.

Macoma (Rexithaerus) secta (Conrad). Coan, Scott, and Bernard, 2000, p. 417, pl. 87.

Macoma secta edulis Carpenter, 1864, p. 639.

Original description.—“Shell triangular or subelliptical, equilateral, compressed, thin, smooth and polished, covered with a very thin shining yellowish epidermis; umbonial slope angulated; posterior extremity broadly and obliquely truncated; cartilage short, thick, inserted on an elongated oblique rib-like callous; margin beneath the cartilage with an ovate gape, appearing as if cut or broken, colour white within and without. Length, two inches. Height, an inch and a quarter.”

Holotype.—ANSP?

Type locality.—San Diego.

Supplementary description.—“Shell large, subquadrate; posterior end longer, broadly truncate, with conspicuous flange on posterodorsal margin; right valve more inflated. The pallial sinuses in valves deep, not detached. Length to 120 mm.” (Coan, Scott, and Bernard, 2000, p. 417)

Geographic range.—Living: British Columbia to Baja California Sur; fossil: Middle California to Baja California Norte.

Geologic range.—Miocene to Holocene.

Occurrence in California.—Miocene: Pancho Rico ((Durham, 1966) Formation, Cierbo and Neroly Sandstones, San Pablo Group (Hall, 1960), and Santa Margarita (Clark, 1916) Formation; Miocene and Pliocene: Etchegoin (Adegoke, 1969) and Towsley (Kern, 1973) Formations; Pliocene and Pleistocene: Fernando (English, 1914), Pico (Winterer and Durham, 1962), San Pedro (Arnold, 1903), and Wildcat (Martin, 1916) Formations; Pleistocene: Unnamed sediments, Baja California Norte and Sur.

Habitat.—“in the intertidal zone to 50 m, deeply infaunal in sand in bays and sheltered offshore situations.” (Coan, Scott, and Bernard, 2000, p. 417)

Subgenus REXITHAERUS?

Macoma (Rexithaerus?) rosa M.A. Hanna, plate 6, figure 9; Plate 6; Plate 6 captions

Macoma rosa M.A. Hanna, 1927, p. 292, pl. 41, figs. 2-5, 8.

Original description.—“Left valve: shell small, thin, only moderately inflated, trapezoidal; ventral margin regularly broadly rounded; anterior regularly but less broadly rounded than the ventral; anterior dorsal margin nearly straight; posterior dorsal margin nearly straight; posterior rostrate; posterior curved outward; a slight umbonal ridge separates two shallow concave areas and forms a lobe on the margin at its termination; beak moderately prominent, situated posterior to the center; ornamentation consists of narrow prominent round-topped concentric ridges, which are separated by nearly flat-bottomed interspaces of about three times the width of the ridges; the concentric ridges bend toward the margin where they cross the umbonal ridge to correspond to the lobation of the margin; lunule and escutcheon prominent; hinge margin narrow; anterior cardinal strong, bifid; posterior cardinal weak; no laterals present; inner margin smooth. Dimensions. Type: Altitude 9 mm., length 11.5 mm.”

Holotype.—UCMP 31094.

Type locality.—UC 3993. San Diego County, Calif.

Comparison.—“Macoma rosa n. sp. differs from Macoma viticola Anderson and Hanna in size and general shape. The beak is more nearly central, and the posterior dorsal slope is nearly straight, while it is rounded in Macoma viticola. In the new species the posterior is bent distinctly outward in the right valve, such is not the case in Anderson and Hanna’s species.” (M.A. Hanna, 1927, p. 292)

Geographic range.—Southern California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: Rose Canyon Shale (M.A. Hanna, 1927).

Macoma (Rexithaerus?) sespeensis Loel and Corey, plate 6, figure 10; Plate 6; Plate 6 captions

Macoma sespeensis Loel and Corey, 1932, p. 228, pl. 43, figs.10, 11, 12a-c.

Original description.—“Shell of medium size, strongly inflate, equivalve, very inequilateral; a strong fold extends from high on umbones to posterior ventral margin, setting off a rounded posterior portion of valves and deeply indenting posterior part of ventral margin; umbones inflate, prominent, anterior; beaks sharp but inconspicuous and proximate; anterior extremity evenly convex and circularly rounded with ventral margin; posterior margin long, nearly straight, with slight concavity just behind umbones, then gently convex to posterior extremity which is very sharply rounded. Type length, 43 mm.; height, 31 mm.; diameter (both valves), 18 mm. Some specimens attain to large size at three localities. Shell evidently thin. Surface was marked by fine incremental lines.”

Holotype.—UCMP 31840.

Type locality.—UC A322. In hard, black, calcareous bed about one mile up Little Sespe Creek from junction with Sespe Creek, Santa Clara Valley, Ventura County, Calif. Vaqueros Formation.

Comparison.—“This species [M. sespeensis] is nearest in form to Macoma moliana Dall (1909) but differs in height, inflation, depth of flexure, and indentation of shell.” (Loel and Corey, 1932, p. 228)

Geographic range.—Southern California.

Geologic range.—Oligocene and Miocene.

Occurrence in California.—Oligocene and Miocene: Vaqueros Formation (Loel and Corey, 1932).

Macoma (Rexithaerus?) diabloensis Clark, plate 6, figure 13; Plate 6; Plate 6 captions

Macoma diabloensis Clark, 1915, p. 475, pl. 61, figs. 8-10.

Original description.—“Shell medium in size, subtrigonal in outline; beaks low, nearly central. Left valve slightly more convex than right. Anterior dorsal edge slightly arcuate; posterior dorsal edge straight; posterior extremity bluntly pointed; anterior end evenly rounded; ventral edge gently and evenly arcuate. Right valve flexed near the posterior extremity; posterior dorsal margin strongly depressed, the narrow depressed area being nearly at right angles to the main surface of the valve and separated from it by a well-defined line; on this narrow, depressed area is a faint groove which does not reach to the beak. Left valve near the posterior extremity bent to the right; posterior margin not depressed. Surface of shell smooth, except for more or less prominent concentric lines of growth. Ligamental groove long, of the M. nasuta type; interior unknown.”

Holotype.—UCMP 11560.

Type locality.—UC 763. South side of Mt. Diablo Anticline, NE 1/4, NE1/4 sec. 29, T 1 S, R 1 E, Contra Costa Co., Calif. San Pablo Formation.

Comparison.—“M. diabloensis differs quite radically in outline from M. nasuta Conrad***the beaks are more central; the posterior extremity is not truncated and the depressed dorsal margins are very different.

“Diabloensis resembles quite closely in outline M. astori Dall***but differs from it in the character of the depressed posterior dorsal margin; also the shell is not so large.

“M. diabloensis differs from M. calcarea Gmelin in the character of the posterior dorsal margin, and in that the beaks are more central.” (Clark, 1915, p. 475)

Geographic range.—Middle California.

Geologic range.—Oligocene and Miocene.

Occurrence in California.—Oligocene and Miocene: Temblor Formation (Adegoke, 1969); Miocene: Cierbo and Neroly Sandstones, San Pablo Group (Hall, 1960) and Santa Margarita Formation (Adegoke, 1969).

Macoma (Rexithaerus?) nasuta jacalitosana Arnold, plate 6, figure 12; Plate 6; Plate 6 captions

Macoma jacalitosana Arnold, 1910, p. 65, pl. 16, fig. 2.

Macoma nasuta (Conrad) var. jacalitosana Arnold. Grant and Gale, 1931, p. 366.

Original description.—“Shell attaining a length of 70 millimeters, oblong, attenuated posteriorly inflated, inequivalve, inequilateral, surface smooth. Beaks slightly anterior to middle, small, tumid, curved slightly forward; anterior extremity regularly rounded; posterior dorsal margin only slightly curved, sloping more steeply from beak than anterior dorsal margin; posterior extremity moderately sharply truncated near base of shell, posterior surface to right valve flexed into a prominent carina or fold which extends from the beak to the posterior angle at base; the carina being separated from the dorsal margin by a space equal in width to nearly one-third the width of the shell; base line curved to conform to flexure of disk, otherwise nearly straight; left valve flexed downward and with carina less prominent and nearer dorsal margin than in right. Surface sculpture by fine sharp incremental lines and occasional lines of interrupted growth.”

Holotype.—USNM 156613.

Type locality.—USGS 4765. Jasper Creek just above Jacalitos Creek, on west side of center SW 1/4, T. 22 S., R. 15 E., Coalinga Quad., Fresno County, Calif.

Comparison.—“M. jacalitosana belongs to the same general group as M nasuta Conrad***but is very much more inflated, narrower posteriorly, and carries the posterior carina or fold much father below the dorsal margin than the latter.” (Arnold, 1910, p. 65)

Geographic range.—Middle California.

Geologic range.—Miocene and Pliocene.

Occurrence in California.—Miocene and Pliocene: Etchegoin Formation (Keen and Bentson, 1944).

Macoma (Rexithaerus?) addicotti Nikas, plate 5, figure 11; Plate 5; Plate 5 captions

Macoma, new species?, aff. M. nasuta (Conrad). Addicott, 1969, p. 72-73, pl. 4, fig. 12.

Macoma addicotti Nikas, 1977, p. 434-437, 6 figs.

Original description.—“The shell is large, thick, oval in outline, anterior end well rounded, posterior end broad and sharply truncated; beak slightly to the posterior of the center of the valve. The external surfaces of both valves sculptured only by irregular concentic growth lines. The ligamental groove extends approximately 3/4 of the way along the dorsal margin, ending at the top of the posterior adductor muscle scar. The pallial sinus of the right valve extends forward from the posterior muscle scar approximately midway to the anterior adductor muscle scar where it curves steeply down to the pallial line. The pallial sinus of the left valve extends from the posterior muscle scar, rising slightly in the center of the valve and then slopes down to the anterior muscle scar. The shell is bent to the right at the posterior ends of both valves. The left valve curves slightly from the umbo to halflway along the ligamental groove, where the curvature increases to a slight hook. The right valve is bent strongly to the right beginning 2/3 of the way along the dorsal margin.”

Holotype.—CAS 55959.

Type locality.—CAS 44020. 763 m east of the intersection of Arastradero Road and Alpine Road, opposite the entrance to the American Institute of Research, Palo Alto, Calif. Palo Alto Quad, 1961 ed. Purisima Formation.

Comparison.—“Macoma addicotti can be readily distinguished from M. nasuta ***Macoma nasuta is narrow dorsally and elongated posteriorly, while M. addicotti is broad and sharply truncated posteriorly. The beak is nearly central in M. nasuta, while in M. addicotti the beak is slightly to the posterior.

“***the flexure on the left valve of M. addicotti begins midway between the umbo and the posterior end of the shell, while on M. nasuta this flexure begins slightly to the anterior of the middle of the shell.

“On the right valve of Macoma addicotti the pallial sinus forms a 70° angle with the pallial line, while the pallial sinus of the right valve of M. nasuta forms a 50° angle with the pallial line. The pallial sinus of the left valve curves down at the center of the shell and forms a 40° angle to the posterior muscle scar, while on M. nasuta the pallial sinus drops at about a 30° angle. The large maximum size of M. addicotti is an important diagnostic characteristic.” (Nikas, 1977, p. 436-437)

Geographic range.—Middle California.

Geologic range.—Pliocene.

Occurrence in California.—Pliocene: Merced(?) and Purisima Formations (Nikas, 1977).

Macoma (Rexithaerus?) nasuta kelseyi Dall, plate 6, figure 11; Plate 6; Plate 6 captions

Macoma kelseyi Dall, 1900a, p. 1052, pl. 49, fig. 7.

Macoma nasuta (Conrad) var. kelseyi Dall. Arnold 1903, p. 164. Grant and Gale, 1931, p. 366.

Macoma nasuta kelseyi Dall. Woodring in Woodring and Bramlette, 1950, p. 65, 87, pl. 20, figs. 2, 8.

Macoma (Macoma) nasuta kelseyi Dall. Hertlein and Grant, 1972, p. 294-295, pl. 52, figs. 5, 9, 11, 12, text fig. 13.

Original description.—“Shell large, solid, heavy, compressed, slightly flexed; beaks subcentral, prominent, pointed; anterior end evenly rounded into an arcuate base and dorsal margin; posterior end lanceolate, the dorsal margin nearly rectilinear; surface sculptured only by strong, rather irregular lines of growth; hinge-plate short, broad, and strong; teeth normal, elongated, large; pallial sinus discrepant in the two valves; left valve with the upper part of the sinus sinuous, extending from the posterior to the anterior adductor, behind which is a thickened, obscure ray; right valve with the sinus short, gibbous, the anterior end rounded, thence the line curves backward before coalescing with the pallial line below; in the left valve the sinus is coincident with the whole of the pallial line below. Long. 86, alt. 56, diam. 20 mm.”

Holotype.—USNM 147690.

Type locality.—City Park, San Diego, Calif. San Diego Formation.

Comparison.—Dall, (1900, p. 1052) and Woodring (in Woodring and Bramlette, 1950, p. 87) believed that the fossil form, M. nasuta kelseyi, differed from the Holocene form, M. nasuta, in its large size, thick shell, and slightly bent posterior end. Hertlein and Grant (1972, p. 294) thought that M. n. kelseyi might be merely a very large form of M. nasuta, but favored its retention as it might be of ecologic or stratigraphic significance. Coan, Scott, and Bernard (2000, p. 420) synonymized M. n. kelseyi with M. nasuta without comment.

“This shell [M. n. kelseyi] is similar to that of typical nasuta, but is narrower, less flexed and the posteior end is somewhat more obliquely truncated.” (Grant and Gale, 1931, p. 366)

Geographic range.—Living: Puget Sound. Washington, to Half Moon Bay, California; Fossil: Southern California.

Geologic range.—Pliocene to Holocene.

Occurrence in California.—Pliocene: Cebada and Graciosa coarse-grained Members, Careaga Sandstone (Woodring in Woodring and Bramlette,1950).

Habitat.—In 5 to 7 m.

Macoma (Rexithaerus?) andersoni Clark, plate 7, figure 1; Plate 7; Plate 7 captions

Macoma andersoni Clark, 1915, p. 473-474, pl. 61, fig. 12. Weaver, 1943, p. 211, pl. 49, fig. 9; pl. 52, fig. 7.

Original description.—“Shell elongate, subovate; beaks posterior to middle, inconspicuous. Posterior dorsal edge slightly concave along ligamental groove, beyond this nearly straight to slightly convex; anterior dorsal edge long and gently convex; anterior end evenly rounded; posterior end bluntly pointed; ventral edge gently convex anteriorly and nearly straight posteriorly. On left valve along posterior margin is a narrow depressed area, which is only obscurely separated from the main surface of the valve; it widens quite perceptibly below the ligamental groove into a flange, somewhat similar to though not so wide or distinct as the flange seen on the posterior edge of M. secta Conrad, a Recent species and one which is also found in the same horizon; right valve slightly flexed and with posterior margin more strongly depressed than on left. Ligamental groove less than half the length of posterior dorsal edge. Surface of valves covered by fine incremental lines and occasional lines of interrupted growth.”

Holotype.—UCMP 11557.

Type locality.—UC 1449. NE cor. sec. 14, T. 1 S., R. 1 W., Mt. Diablo Quad., Contra Costa Coutny, Calif. San Pablo Formation.

Comparison.—“M. andersoni is of the same general type as M. indentata Carpenter, a Recent species on the West Coast; it differs in that the ventral edge is not so arcuate, and does not have the distinct concavity seen on the latter along the line of flexure***

“M. Anderson is found in the same general horizon as M. diabloensis, n. sp.***it is longer in proportion to the height; the right valve is not so strongly flexed nor so strongly depressed along the posterior dorsal margin. M. diabloensis lacks the distinct flange along the posterior dorsal margin, seen on M. andersoni.

“M. andersoni somewhat resembles M. vanvlecki Arnold***It differs, however, in that the depressed posterior margin is narrower and is not sharply defined by a carina as is the case with M. vanvlecki; the posterior flexure of the right valve is not so great; the ventral edge is straighter, lacking the strong concavity along the line of flexure seen on M. vanvlecki.” (Clark, 1915, p. 474)

Geographic range.—Coos Bay, Oregon; middle California.

Geologic range.—Miocene.

Occurrence in California.—Miocene: Briones (Trask, 1922), Cierbo and Neroly Sandstones (Hall, 1960), San Pablo Group, McClure Shale Member, Monterey Group (Adegoke, 1969), and Santa Margarita Formation (Addicott and others, 1978).

Macoma (Rexithaerus?) vanvlecki Arnold, plate 7, figure 2; Plate 7; Plate 7 captions

Macoma vanvlecki Arnold, 1910, p. 65, pl. 12, fig. 2; pl. 16, fig. 1. Nomland, 1917a, p. 246, pl. 8, figs. 3, 3a. Grant and Gale, 1931, p. 375.

Original description.—“Shell averaging between 50 and 60 millimeters in length, elongate oval, attenuated anteriorly beaks anterior, inequivalve, tumid, the left valve much more tumid than the right and having the anterior extremity flexed upward instead of downward. Beak, small and not prominent, located a little over two-fifths the length of shell from anterior extremity; anterior dorsal margin faintly angulated in middle sloping steeply downward from beak toward extremity which is sharply angulated at a point somewhat below the horizontal medial line of the valve; posterior extremity nearly straight, posterior extremity curved, the point of greatest convexity occurring above middle line of valve; base slightly curved and practically parallel with posterior dorsal margin except for faint convex curve caused by the flexing of the valve; a prominent angle joins the beaks and the anterior extremity; in the left valve this angle flexes upward, in the right valve downward. Surface smooth except for fine incremental lines. Hinge unknown.”

Holotype.—USNM 165576.

Type locality.—USGS 4763. 200 yards north of Jacalitos Creek crossing on Stone Canyon-Coalinga road, 14 miles southwest of Coalinga, Fresno County, Calif. Etchegoin Formation.

Comparison.—“M. vanvalecki is more closely related to M. indentata Carpenter***than to any other member of this genus from the west coast, but may be distinguished by its narrower outline, relatively longer anterior extremity, and less show of flexuosity on the anterior ventral margin.” (Arnold, 1910, p 65)

Geographic range.—Southern California.

Geologic range.—Miocene and Pliocene.

Occurrence in California.—Miocene and Pliocene: Etchegoin Formation (Adegoke, 1969).

Subgenus MACOPLOMA Pilsbry and Olsson, 1941

“Shell elongate, nearly equivalve, the left valve a lilttle larger and more convex than the right; surface with the granulation of Periploma, developed most strongly on the posterior area, finer or absent from the rest of the surface; hinge of Macoma, with a small cardinal tooth in the left valve and no laterals.” (Pilsbry and Olsson, 1941)

Macoma (Macoploma) medioamericana Olsson, plate 7, figure 3; Plate 7; Plate 7 captions

Macoma (Macoploma) medioamericana Olsson, 1942, p. 196, pl. 17, fig. 8. Hertlein and Grant, 1972, p. 295, pl. 52, figs. 6, 8.

Psammacoma (Macoploma) medioamericana Olsson, 1961, p. 416.

Original description.—“Shell of medium or large size, elongate, delicate; the valves are subequal, the left being slightly larger and more convex than the right which is somewhat flexed or depressed in the middle; beaks, placed at the posterior one-third, are small and pointed; anterior side nearly twice the length of the posterior, obliquely rounded at the end; posterior side somewhat narrowed, obliquely truncated at the end; surface is marked with lines of growth, smoother in the middle, coarse and more or less granulose on the sides; each valve has a narrow, submarginal zone at the posterior end, its surface earthy in appearance and bordered anteriorly by a line of coarse granules; hinge unknown. Length, 62 mm.; height, 30 mm.; diameter, 12 mm.”

Holotype.—Paleo. Research Inst. 5004.

Type locality.—Quebrada Penitas, Costa Rica.

Supplementary description.—“The shell is elongate and shaped much like the species of Psammacoma, but the posterior slope has concentric riblets and is dotted with granules.” (Keen, 1971, p. 227)

Geographic range.—Living from Gulfo de California to Ecuador; fossil from southern California to Costa Rica.

Geologic range.—Pliocene to Holocene.

Occurrence in California.—Pliocene: San Diego Formation (Hertlein and Grant, 1972)

Habitat.—Intertidal to 82 m (Hertlein and Grant, 1972, p. 295)

SUBGENUS?

Macoma (Subgenus?) lorenzoensis (Arnold), plate 7, figure 4; Plate 7; Plate 7 captions

Tellina lorenzoensis Arnold, 1908, p. 367, pl. 33, fig. 1. Clark, 1915, p. 15. Arnold, 1918, p. 152.

Macoma lorenzoensis (Arnold). Clark, 1925, p. 96, pl. 12, fig. 10. Tegland, 1933, p.119, pl. 9, fig. 1.

Original description.—“Shell attaining a length of 40 mm., width a little over five-eighths of length, oblong, compressed, slightly inequivalve, anterior end evenly rounded, posterior end biangular and narrower than anterior; umbo small, central, though sometimes, as in type, placed a little in front of middle; sides making an angle of 125° at the umbo; anterior dorsal margin very gently curved near umbo, becoming rapidly more curved near extremities; ventral dorsal margin very gently curved for whole length to upper posterior angle; a moderately sharp fold, on which the lines of growth are particularly prominent, extends from the umbo to the lower posterior angle; a faint indication of a reentrant angle often occurs in the margin at the end of the fold; base nearly straight, curving quite rapidly at ends. Surface sculptured by numerous slightly unequal concentric lines. Left valve similar to right except that instead of being very slightly flexed upward at the posterior extremity, it is flexed downward.”

Holotype.—USNM 165439.

Type locality.—Southeast branch of Waddell Creek, Big Basin, Santa Cruz County, Calif.

Geographic range.—Middle California.

Geologic range.—Eocene and Oligocene.

Occurrence in California.—Eocene and Oligocene: San Lorenzo Formation (Arnold, 1908).

Habitat.—“***in the intertidal zone to 50 m, in exposed to sheltered situations, usually in sand or silt.” (Coan, Scott, and Bernard, 2000, p. 420)

“According to Fitch, this clam always lies on the left side and its siphons are extended to the surface for feeding and are freely withdrawn and re-extended to a different spot.” (Hertlein and Grant, 1972, p. 294)

Macoma (Subgenus?) viticola Anderson and GD. Hanna, plate 7, figure 5; Plate 7; Plate 7 captions

Tellina californica Gabb. Dickerson, 1915, p. 43, pl. 4, fig. 3. Not Gabb, 1864, pl. 30, fig. 245.

Macoma viticola Anderson and GD. Hanna, 1925, p. 157, pl. 2, fig. 12. M.A. Hanna, 1927, p. 293.

Original description.—“Shell small, moderately inflated, inequilateral, very thin; truncated posteriorly, having a shallow depression immediately before truncation in right valve; basal and anterior margins regularly rounded; sculpture consisting of very fine growth lines, slightly uneven; apical angle 128°. Length, 11.9 mm.; height, 8.7 mm.; thickness, 2 mm.; right valve.”

Holotype.—CAS 1701.

Type locality.—CAS 244. Live Oak Creek, Kern County, Calif.

Geographic range.—Southern California.

Geologic range.—Eocene.

Occurrence in California.—Eocene: La Jolla (M.A. Hanna, 1927) and Tejon (Anderson and Hanna, 1925) Formations.

Macoma (Subgenus?) wilcoxi Hall and Ambrose, plate 7, figure 6; Plate 7; Plate 7 captions

Macoma wilcoxi Hall and Ambrose, 1916, p. 81. Wiedey, 1929, pl. 1, fig. 4

Original description.—“Right valve; shell thin, elongate, inequilateral; surface smooth; beaks, small, low, pointed, nearly medial, curved slightly toward posterior end; anterior extremely regularly rounded; posterior dorsal margin straight, sloping more steeply from beak than anterior dorsal margin toward extremity which is angulated at a point somewhat below the horizontal medial line of the valve; base curved. Hinge unknown, interior inaccessible.

“Long., 31 mm.; lat., 18 mm.; diameter, 5 mm.

“The angular posterior extremity gives it a distinctive shape.”

Holotype.—SU 506.

Type locality.—North limb, Haywards Pass Syncline, Pleasanton Quad., Alameda Co., Calif. Briones Sandstone (Keen and Bentson, 1944).

Geographic range.—Middle California.

Geologic range.—Miocene.

Occurrence in California.—Miocene: Briones Sandstone, San Pablo Group (Wiedey, 1928).

Macoma (Subgenus?) pabloensis Clark, plate 7, figure 8; Plate 7; Plate 7 captions

Original description.—“Shell small, sub-equilateral, subtrigonal in outline; beaks inconspicuous and central. Anterior dorsal edge very slightly arcuate; posterior dorsal edge straight; ventral edge regularly and rather stongly arcuate; posterior end bluntly pointed; anterior end broadly and evenly rounded. Surface of valves marked by medium fine incremental lines. Right valve slightly flexed near the posterior extremity; bordering the posterior dorsal edge is a narrow depressed area on which is a faint groove extending from the posterior extremity about half way to the beaks; this depressed area is separated from the remainder of the surface by a raised line or ridge. Left valve with an obscure, narrow, posterior depressed area on which there is usually a faint groove corresponding to the groove seen on the depressed area of the right valve. Shell near the posterior end slightly twisted to the right. Ligamanetal groove rather long, about half the length of posterior dorsal edge. Of the two cardinal teeth in right valve, the posterior cardinal is the larger and is bifid; in the left valve the anterior cardinal is the larger and is bifid.”

“Type specimen: length, 13 mm.; height, 13 mm.; diameter of both valves, 8 mm.”

Holotype.—UCMP 11563.

Type locality.—UC 1631. About 1/4 mile east of Rodeo, Napa quadrangle, Contra Costa Co., Calif. San Pablo Formation.

Geographic range.—Middle California.

Geologic range.—Miocene.

Occurrence in California.—Miocene: San Pablo Formation (Clark, 1915).

Genus LEPORIMETIS Iredale, 1930

“Shell oblique, inflated, inequilateral. Posterior end rounded to broadly truncate, set off by dorsal radial sulcus. Surface with commarginal riblets and frequently with radial striae. Escutcheon and lunule may be present. Two small cardinal teeth present in each valve; lateral teeth absent. Pallial sinus deep.”

Leporimetis rostellata (Clark), plate 7, figure 7; Plate 7; Plate 7 captions

Metis rostellata Clark, 1918, p.154, pl. 9, fig. 7.

Apolymetis rostellata (Clark). Keen and Benston, 1944, p. 67.

Original description.—“Shell medium in size, ventricose, equivalved, broadly subrostrate posteriorly, broadly rounded in front; beaks rather inconspicuous, situated within the anterior third of the shell. Anterior dorsal edge very short, gently convex and with no angulation or change in slope between it and the rounded anterior end; posterior end narrow, broadly truncate. Surface rather strongly excavated just anterior to the beaks; covered by low, sharp, somewhat irregular lines of growth. Posterior dorsal margin on left valve strongly depressed and separated from main portion of shell by a distinct ridge, which reaches from the beak to the posterior end; a broad, shallow sinus anterior to this ridge and parallel with it. A good right valve of the species was not obtained but it seems very probable, as on many species of this genus, that on this valve there would be a sinus near and parallel to the posterior dorsal margin, corresponding to the ridge on left valve. Two well-developed cardinals in left valve.”

Holotype.—UCMP 11120.

Type locality.—UC 1131. Southwest of town of Walnut Creek 1/2 mile, in creek bed, Long 122°4’8”, Lat. 37 53’7”, Concord Quad., Contra Costa County, Calif.

Comparison.—“This species is quite unique, differing from most of the other species of this genus in having the beaks so far anterior.” (Clark, 1918, p. 154)

Geographic range.—Middle California.

Geologic range.—Eocene, Oligocene, and Miocene(?).

Occurrence in California.—Eocene and Oligocene: San Emigdio Formation (DeLise, 1967); Miocene(?) San Ramon Formation Formation (Keen and Bentson, 1944).

Leporimetis dombei (Hanley), plate 7, figure 9; Plate 7; Plate 7 captions

Tellina dombei Hanley, 1844, p. 144.

Psammotreta dombei (Hanley). Olsson, 1961, p. 412, pl. 74, fig. 2; pl. 85, figs. 1-1b.

Flomimetis dombei (Hanley, 1844). Keen, 1971, p. 227, fig. 558.

Tellina excavata Hanley, 1844, p. 144.

Metis excavata (Sowerby). Hanna, 1926, p. 467, pl. 23, fig. 6. Grant and Gale, 1931, p. 364.

Hypotype.—UCMP 32278.

Supplementary description.—The shell is ovate-oblong, the posterior side shorter, its dorsal margin descending into a rounded and slightly flexed end; generally with a small open gap along the anterior margin. The valves are nearly alike in shape and inflation, the left valve is a trifle smaller only. Both valves are convex along the anterior-umbonal slope, impressed behind. Surface smooth except for the lines of growth which are irregularly distributed and sometimes set off in bands by the deeper resting marks. ***The pallial sinus is large, highest in the middle, united below with the pallial line. The ligament scar immersed.” Olsson, 1961, p. 412)

Geographic range.—Southern California.

Geologic range.—Miocene or Pliocene.

Occurrence in California.—Miocene or Pliocene: Latrania Formation (Olsson, 1961).

Leporimetis obesa (Deshayes), plate 7, figure 10; Plate 7; Plate 7 captions

Tellina obesa Deshayes, 1855, p. 354.

Scrobicularia biangulata Carpenter, 1856, p. 230.

Metis alta Conrad. Arnold, 1903, p. 160. Clark, 1915, pl. 64, fig.2. I.S. Oldroyd, 1924, p. 169, pl. 57, fig. 3.

Apolymetis biangulata (Carpenter). Durham, 1950, p. 89, pl. 24, fig. 1; pl. 25, fig. 12. Palmer, 1958, p. 107, pl. 14, fig. 5.

Florimetis biangulata (Carpenter). Moore, 1968, p. 64, pl. 30, figs. a, b. Hertlein and Grant, 1972, p. 298, pl. 53, figs. 14, 17, 19.

Leporimetis obesa (Deshayes, 1855). Coan, Scott, and Bernard, 2000, p. 420, pl. 87.

Original description.—

Holotype.—

Type locality.—

Supplementary description.—“Shell subquadrate, subequilateral, inflated, heavy; posterior dorsal margin set off by prominent radial fold. Sculpture of closely spaced, low commarginal ribs and undulations. Interior of valves usually flushed from orange to yellow. Pallial sinus deep in both valves, substantially detached. Length to 112 mm.” (Coan, Scott, and Bernard, 2000, p. 420)

Geographic range.—Living: Southern California to Baja California Sur; fossil: Southern California to Baja California Sur.

Geologic range.—Miocene to Holocene.

Occurrence in California.—Miocene: Cierbo and Neroly Sandstones, San Pablo Group (Hall, 1960)and Santa Margarita Formation (Addicott, and Vedder, 1963); Miocene and Pliocene: Imperial Formation (Powell, 1988); Pliocene: San Diego Formation (Hertlein and Grant, 1972); Pliocene and Pleistocene: Fernando (Durham and Yerkes, 1964) and Pico (Winterer and Durham, 1962) Formations; Pleistocene: unnamed sediments in southern California (Kanakoff and Emerson, 1959; Moore, 1968).

Habitat.—Subtidal zone to 50 m, in sand. (Coan, Scott, and Bernard, 2000, p. 420). Often along the outer coast in coarse sand and gravel or near boulders. (Hertlein and Grant, 1972, p. 298)

Supplementary description.—“oval, moderately compressed***Left valve with a shllow, radial groove near the posterior end. Right valve with a corresponding ridge at the end of which the margin of the shell is shallowly notched.” (Abbott, 1974, p. 509)

Habitat.—Found 6 inches in fine sand from low-tide mark to 125 fathoms [229 m]. (Abbott, 1974, p. 509)

Leporimetis cognata clarki (Durham), plate 7, figure 11; Plate 7; Plate 7 captions

Apolymetis clarki Durham, 1950, p. 90, pl. 24, fig. 12; pl. 25, fig. 14.

Florimetis cognata clarki Durham. Hertlein and Grant, 1972, p. 298.

Original description.—“Shell externally similar to that of A. Biangulata (Carpenter) except that the ligament is not quite so long and internally the hinge plate is only about half as wide; with the two anterior cardinals of right valve in same position, but about half again as high; posterior cardinal and lateral of right valve obsolete (present in A. biangulata); ligamental groove very shallow, about half the depth of the aforementioned species; beaks central.”

Holotype.—UCMP 32615.

Type locality.—UC A3582. From 20-foot terrace level extending from loc. A3581 to beach, west of Santa Inez Point, Bahía Santa Inez, Baja California Sur.

Comparison.—“Apolymetis excavata Sowerby (1867) is much more abruptly truncated posteriorly and less inflated.” (Durham, 1950, p. 90)

Geographic range.—Southern California to Baja California Sur.

Geologic range.—Pliocene to Holocene.

Occurrence in Baja California.—Pliocene: Marquer Formation (Durham, 1950).

[Last updated July 6, 2003.]

To title page of Tertiary Marine Pelecypods of California and Baja California