Argopecten eccentricus caimiticus (Maury, 1917)
MAURY, C. J. 1917. Santo Domingo Type Sections and Fossils. Part 1: Mollusca. Bulletins of American Paleontology, 5 (29): 166-415, pls. 1-39. [p. 353, pl. 34, fig. 12]
1917 Pecten caimitica Maury, 1917
C. J. Maury, 1917, plate 34.
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«We collected a single valve of a Pecten examined by Dr. Dall and not identified by him with any in the National Museum from Bowden or Santo Domingo. The shell is suborbicular, slightly oblique, convex in the umbonal region but elsewhere rather compressed; surface ornamented with twenty-two narrow, rounded, radial ribs with narrower, concave interspaces; ribs and interspaces marked only by concentric, looped growth lines; ears very small, nearly equal, radially threaded. Length 20, altitude 20, semidiameter 5 mm. The species is distinguished by it more numerous ribs and very small ears.
Locality.— (Exp'd '16) Zone I, Rio Cana at Caimito». CARLOTTA JOAQUINA MAURY, 1917
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«Comparisons.— Argopecten eccentricus caimiticus is similar to A. e. eccentricus but smaller, more gibbous, with broader ribs lacking medial troughs on the right valve and more trigonal, somewhat rugose ribs on the left valve. Compared to the extant species A. nucleus, A. e. caimiticus has relatively smaller auricles and the costae on disk flanks are somewhat finer, forming a less complete transition from the size of costae on auricles to the size of ribs on the adjacent disk.
Evolution.— See under Argopecten eccentricus eccentricus. Occurrence.— Argopecten eccentricus caimiticus occurs in the uppermost Miocene and lower Pliocene in the shallow-water phases of the Gurabo Formation in a stratigraphic position that is inferred to be above that of A. e. eccentricus. Argopecten e. caimiticus is abundant on the Río Cana beginning in the vicinity of the "Arca beds" 228 m above the base of the section and extending to the upper Gurabo Formation at 427 m above the base of the section (Table 7). The only occurrence in the Río Gurabo section is at 222-226 m above the base of the section (NMB 16808). Above this level, this subspecies was apparently excluded by deep-water conditions. At locality TU 1250 on the Río Verde and locality TU 1405 in the Santiago area, A. e. caimiticus occurs in gravity flows that carried sediments of the shallow-water Cercado facies into the Gurabo facies. Distribution.— Argopecten eccentricus caimiticus has thus far not been recognized outside of the Dominican Republic». 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. 52]
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Argopecten eccentricus caimiticus (Maury, 1917); T. R. Waller, 2011, Neogene Paleontology of the Northern Dominican Republic, plate 6, figures 1-7.
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