Catalogue of the Living Bivalvia of the Eastern Pacific Ocean ...

32. Chlamys islandica (Müller 1776) according to MacNeil (1967) does
not occur in the Pacific Ocean or Bering Sea, though Grau (1959) considered
C. behringiana (Middendorff 1849) and C. albida (Arnold 1906) to be
subspecies of C. islandica. I believe them to be distinct but on the other
hand, species proposed by MacNeil, appear tome to be mere variants of C.
islandica.
33. Hinnites (DeFrance 1821) is usually accorded full generic status. I am
unable to find distinguishing characters and do not consider the late cementation
and idiomorphic growth sufficient to accord more than subgeneric
separation.
34. Semipallium zeteki (Hertlein 1935) was proposed as a replacement
name for the preoccupied Pecten digitatus (Hinds 1844), but nothing corresponding
to the description is known from the eastern Pacific. The taxon is
probably referable to S. vexillum (Reeve 1853) from the western Pacific.
35. Cyclopecten imbrifer (Lovén 1847) probably does not occur in the
eastern Pacific, but is included on the basis of material from Oregon that may
be a new species, but the relationship to C. benthalis (Grau 1959) must be
resolved.
36. Cyclopecten incotigruus (Dall 1916) is known from the holotype only;
though the type locality is cited as San Diego, California, the specimen label
states Cedros Island, Baja California.
37. Cyclopecten vitreus (Gmelin 1791) seems to be the species with the
widest distribution, but may include a complex of species that may be
separable with the study of shell ultrastructure.
38. Pecten berlyi nom. nov. is proposed for the preoccupied P. lunaris
(Berry 1963).
39. Spondylus tenebrosus (Reeve 1856) has been recorded from Clipperton
Island (Salvat & Ehrhardt 1970).
40. Spondylus victoriae (Sowerby 1859) is widespread throughout the
Gulf of California and is well represented in the collection of the Allan
Hancock Foundation. Though overlooked by modern workers, the name
was used for Recent and Pliocene species by Durham (1950).
41. Anomia chinensis (Philippi 1849) was incidentally introduced from
Japan to Willapa Bay, Washington, but did not become established.
42. Pododesmus cepio (Gray 1850) is frequently merged with P. macrochisma
(Deshayes 1839) which is confined to Alaska.
43. Lucina approximata (Dall 1901) probably is represented by a complex
of several species.
44. Lucina mazatlanica (Carpenter 1857) requires careful evaluation. It
has been reported from the Gulf of California in 1043 m (Emerson and Puffer
1957) ,
45. Thyasirinae subfamily nov. is proposed for members of the family
Thyasiridae that are deeply infaunal, usually in regions of low productivity
and low oxygen tension. The unsculptured shell has sharp dorsal folds
accompanied by one or two radial sulci. The most profound modifications
are in the soft parts, particularly the long vermiform foot, with terminal
secretory bulb, which forms the mucoid inhalant tube. The anterior adductor
muscle is elongated by the rotation of the body relative to the shell. The type
genus is Thyasira Leach in Lamarck 1818. Included genera are Conchocele
(Gabb 1866), Maorithyas (Fleming 1950), Parathyasira (Iredale 1930) and
Philis (Fischer 1861).
46. Conchocele excavata (Dall 1901) is usually placed in Thyasira sensu
stricto, but the shell and anatomy show that it should be assigned to
Conchocele. Shallow water (18-90 m) records from the Gulf of California
(Parker 1964) are not this species.
47. Axinopsidinae subfamily nov. is proposed for members of the family
Thyasiridae that are members of the shallow infauna. Unlike the Thyasirininae,
the group lacks shell folds or sulci, the hinge is strengthened by
tubercles or pseudodentition, and the lunule is well developed. The subfamilies
have arborescent digestive diverticula, but the foot is much shorter
68
in the Axinopsininae and lacks the hypertrophied terminal portion. I consider
the proposed subfamily, dating from the Pliocene, only distantly related to
the Thyasirinae which arose in the Cretaceous. The type genus is Axinopsida
Keen and Chavan in Chavan 1951. Included genera are Adontorhina (Berry
1947) and Axinulus (Verrill & Bush 1898).
48. Felaniella parilis (Conrad 1848), described as a Miocene fossil, was
first united with living material by Grant & Gale (1931) though largely
ignored by subsequent workers, review of a large suite of living and fossil
material from California and Washington (Pliocene), confirms my opinion.
49. Kelliinae subfamily nov. is proposed to contain members of the family
Kelliidae with strong dentition, mantle folds not extendable over the shell
surface and the foot not modified into a wide creeping sole. The type genus is
Kellia (Turton 1822). Included genera are Aligena (Lea 1846), Diplodontina
(Stempell 1899), and Odontogena Cowan 1964.
50. Aligena pisum (Dall 1908) is known only from a left valve, eroded and
immature. It has been assigned to Axinulus by Harry (1969), but certainly is
not a member of that genus. This taxon may best be considered a nomen
dubium.
51. Borniinae subfamily nov. is proposed to contain the genera Bornia
(Philippi 1836), Rhamphidonta (Bernard 1975) and Solecardia (Conrad
1849). Unlike other members of the family Kelliidae, this group has the
hinge comparatively weakly developed, the shell thin and elongated. The
mantle inner fold is capable of great extension to cover the entire shell
valves, and the foot modified into a wide creeping disc. The type genus is
Bornia (Philippi 1836).
52. Ercyiniinae subfamily nom, trans!, is proposed for member genera of
the family Lasaeidae with elongated compressed shells, weak to moderate
hinge plate, laterals lamelliform, ligament extending backwards. The type
genus is Erycina Lamarck 1805. Also included is Amerycina Chavan 1959.
53. Lasaeinae subfamily nom, trans!, is proposed for the distinctive genus
Lasaea (Brown 1827) of the family Lasaeidae. The subfamily is characterized
by a rounded minute shell, nearly vertical beaks, and a thick, heavy
hinge with a protruding cardinal in the left valve. The lateral teeth are similar
in both valves and continuous with other teeth.
54. Montacutinae subfamily nom, trans!, is proposed for genera of the
family Montacutidae with subequilateral shells, thickened lateral teeth and
minute resilium. The type genus is Montacuta (Turton 1822). The other
included genus is Montacutona (Yamamoto and Habe 1959).
55. Mysellinae subfamily nov. is proposed for the very distinct genus
Mysella (Angas 1877) which should probably be divided into several
genera. All species have a large resilifer, frequently bounded by raised
margins or teeth forming a chondrophore-like structure.
56. Orobitellinae subfamily nov. is proposed for a number of genera of the
family Montacutidae, with usually inequilateral shells and oblique poorly
developed resilifers. The right valve displays a strong anterior lateral tooth.
The type genus is Orobitella (Dall 1900). Included genera are lsorobitella
(Keen 1962), Neaeromya (Gabb 1873), Pythinella (Dall 1899), and tentatively,
Scioberetia (Bernard 1895).
57.Thecodontinae subfamily nov. is proposed for very inequilateral genera
of the Montacutidae, with projecting prosogyrate beaks, resilifer oblique.
Left valve with anterior lateral tooth slightly serrated and curved, following
shell margin. The type genus is Thecodonta (A.Adams 1864). The east
Pacific representative is Pristes (Carpenter 1864).
58. Basterotia quadrata (Hinds 1843), described without locality.
According to Olsson (1961) it was cited by Dall as a member of the east
Pacific fauna. I am unable to find mention of any such species by Dall, but
Paetel (1890) did include it in his catalogue. The species is a common warm
water west Atlantic Ocean and Caribbean species.
59. Cyclocardia gouldii (Dall 1903) was described from 1503m off San
Diego, California, but no other material from this well-collected area
matches the type material. I consider this to be a misplaced Atlantic C.
borealis (Conrad 1831), the elongate form sometimes accorded subspecific
status as C. borealis novangliae (Morse 1869). This conclusion may be