Paraleptopecten bellilamellatus 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. 108, pl. 41, figs. 6, 6a, 7, 7a]
1906 Pecten (Chlamys) bellilamellatus Arnold, 1906
R. Arnold, 1906, plate 41.
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«Description.— Shell averaging about 18 millimeters in altitude, about as long as high, equivalve, both valves moderately convex, inequilateral; sides nearly straight; margins not serrate. Right valve with 15 or 16 prominent narrow, sharply convex-topped ribs with sloping sides; interspaces much wider than ribs, with narrow, flat bottoms; surface sculptured by numerous, regular, equidistant, thin, concentric, imbricating lamellae, which cut squarely across the bottoms of the interspaces, curve convexly toward the umbo on the sides of the ribs, and loop gracefully downward away from the umbo on the tops; hinge line equal to the length of the disk; ears equal in length; anterior ear convexly truncated, separated from the disk by a deep, sharply defined, byssal notch, and sculptured by fine, regular, incremental lamellae and five or six subequal radials; posterior ear acutely pointed, radially striate, and with incremental sculpture similar to but not quite as prominent as that of the anterior. Left valve similar to right; anterior ear more prominently sculptured, both radially and concentrically, than the posterior.
Dimensions.— Alt. 18 mm.; long. 18 mm.; hinge line 18 mm.; diameter 8 mm.; umbonal angle 100º. This species is characterized by its small size when adult, long hinge line, narrow, sharply topped ribs and beautifully curved incremental lamellae. It is easily distinguishable from P. latiauritus and varieties, with which it is allied, by the above enumerated characteristics. P. bellilamellatus is so far known only from the Pliocene at Pacific Beach, San Diego, where it is associated with P. healeyi, P. stearnsii, etc. Type in the collection of Delos Arnold. RANGE
Pliocene. Pacific Beach, San Diego County (Arnold).»
RALPH ARNOLD, 1906
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«Paraleptopecten bellilamellatus (Arnold, 1906). Type locality: Pacific Beach, San Diego, California, San Diego Formation (Moore, 1984: B43). Geographic range: middle California to Baja California Sur, in Merced, San Diego, Almejas, and Purisima formations (Moore, 1984: B43). Age: late Miocene to Pleistocene. See Carreño & Smith (2007) regarding stratigraphic refinements of the "Purisima Formation."»
WALLER, T. R. 2011. Neogene Paleontology of the Northern Dominican Republic. 24. Propeamussiidae and Pectinidae (Mollusca: Bivalvia: Pectinoidea) of the Cibao Valley. Bulletins of American Paleontology, 381: 1-197, pls. 1-18. [p. 139]
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Pecten (Chlamys) bellilamellatus Arnold; A. Arnold, 1907, New and characteristic species of fossil mollusks from the oil-bearing Tertiary formations of Southern California, plate 50, figure 14.
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«Holotype.— CAS/SU 35.
Type Locality.— Pacific Beach, San Diego, San Diego County, Calif. San Diego Formation, Pliocene. Comparison.— The small size, long hinge line, narrow, sharply topped ribs, and beautifully curved incremental lamellae are characters which separate L. bellilamellatus from L. latiaurata and L. delosi (Arnold). (Arnold, 1906, p. 108) Comments.— The holotype is a very small, thin-shelled, double-valved specimen. The hinge line is almost as long as the valve. The entire surface of the right-valve disk bears imbricated, concentric lamellae. The lamellae are at right angles to the ribs in the bottom of the interspaces, loop up toward the dorsal margin on the sides of the ribs, and then loop down toward the ventral margin on the tops of the ribs. A ctenolium is exposed along the junction of the right auricle and the disk. The left valve ribs are identical to those on the right valve, but the microsculpture is barely visible. Geographic range.— Middle California to Baja California Sur. Geologic range. — Miocene to Pleistocene. Occurrence in the Californias.—Miocene and Pliocene: Purisima Formation (Arnold, 1906); Pliocene: Almejas (Minch and others, 1976) and San Diego (Hertlein and Grant, 1922) Formations; Pliocene and Pleistocene: Merced Formation (Arnold, 1906).» MOORE, E. J. 1984. Tertiary Marine Pelecypods of California: Propeamussidae and Pectinidae. United States Geological SurveyProfessional Paper, 1228-B: iv + B1-B112, figs. 1-2, pls. 1-42. [p. B43]
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Leptopecten bellilamellatus (Arnold); E. J. Moore, 1984, Tertiary Marine Pelecypods of California, plate 13, figures 3, 6.
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