Lituyapecten turneri (Arnold, 1906)
ARNOLD, R. 1906. The Tertiary and Quaternary pectens of California. United States Geological Survey Professional Paper, 47: 1-264, pls. 1-53 [p. 106, pl. 34, fig. 4; pl. 35, fig. 2-3]
1906 Pecten (Patinopecten) turneri Arnold, 1906
R. Arnold, 1906, plates 34, 35.
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«Description.— Shell averaging about 70 to 80 millimeters in altitude, length same as height, both valves equally compressed, equilateral, and with smooth margins; base regularly rounded; sides nearly straight and sloping at a rather low angle. Right valve with eighteen to twenty-two high, narrow, flat-topped, concave-sided ribs, which, in most cases, show a distinct medial sulcus after reaching a length of 30 or 35 millimeters; interspaces much wider than ribs, round bottomed and sometimes ornamented near the end by a faint intercalary riblet; whole surface of disk finely concentrically striated; hinge line slightly longer than one-half length of disk; ears equal, rectangularly truncated; anterior ear sculptured by four or five prominent radiating ridges and numerous tine incremental lines; byssal notch shallow but distinct; posterior ear with sculpture similar to anterior. Left valve with narrow rounded ribs, which are separated by round-bottomed and concave-sided interspaces much wider than the ribs; surface sculptured by fine, distinct, wavy, concentric lines; ears as in right valve, except lacking byssal notch. Hinge as in P. caurinus.
Dimensions.— Alt. 65 mm.; long. 65 mm.; hinge line 35 mm.; diameter 6 mm. The type is a smaller specimen than the average of this species. P. turneri is allied to the group of which P. caurinus is the commonest representative. Its diagnostic characteristics are its small size for one of this group, narrow, sulcated ribs on right valve and radially striate ears. Found in the Pliocene at Arroyo San Antonio, near Tomales Bay, Marin County, by Dr. H. W. Turner, late of the United States Geological Survey, after whom it is named. The type, which is figured, is now in the collection of the department of geology, Leland Stanford Junior University. RANGE
Pliocene. Tomales Bay, Marin County (Turner).»
RALPH ARNOLD, 1906
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«Lituyapecten turneri (Arnold) has only been reported from the Merced Formation (Arnold, 1906; Dickerson, 1922) and the Purisima Formation (Durham and Morgan, 1978). The Purisima Formation occurrence of Moore (1984) citing Arnold (1906) as authority is not correct; Arnold (1906) listed this species only from the Merced Formation. But it was reported from the Purisima Formation by Ashley (1895a) (as Pecten propatulus Conrad) from Lobitos Creek, Purisima [Creek?], and Tunitas Creek (also by Martin (1916) from Purisima Creek). Durham and Morgan (1978) reported it from the Tahana Member in San Mateo County.»
POWELL II, C. L. 1998. The Purisima Formation and related rocks (upper Miocene - Pliocene), greater San Francisco Bay area, central California. Review of literature and USGS collection (now housed at the Museum of Paleontology, University of California, Berkeley). United States Geological Survey Open-file Report, 98-594, 102 p. [p. 65]
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«Comparison.— "Patinopecten turneri Arnold, * * * was regarded by Grant and Gale * * * as a synonym of purisimaensis. If Grant and Gale were influenced by an error in Arnold's statements about his figured specimens they did not say so. Arnold figured three specimens, two of them as right valves and one as a left valve; however, all three of Arnold's specimens are left valves. This gave him an erroneous concept of his supposed new species and made it appear to be very different from purisimaensis. Actually purisimaensis and turneri are closely related, but some good specimens of turneri * * * show a well-defined sulcus on the right valve ribs that is not found in purisimaensis. These species should probably be kept separate." (MacNeil, 1961, p. 233)
Geographic range.— Middle California. Geologic range.— Miocene to Pleistocene. Occurrence in California.— Miocene and Pliocene: Purisima (Arnold, 1906), and Tahana Member, Purisima (Durham and Morgan, 1978) Formation; Pliocene and Pleistocene: Merced Formation (Dickerson, 1922; Keen and Bentson, 1944).» MOORE, E. J. 1984. Tertiary Marine Pelecypods of California: Propeamussidae and Pectinidae. United States Geological Survey Professional Paper, 1228-B: iv + B1-B112, figs. 1-2, pls. 1-42. [p. B87]
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Lituyapecten turneri (Arnold); E. J. Moore, 1984, Tertiary Marine Pelecypods of California: Propeamussidae and Pectinidae, plate 37, figures 1, 2.
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