Pernopecten yini Newell & Boyd, 1995
NEWELL, N. D. & D. W. BOYD. 1995. Pectinoid bivalves of the Permian-Triassic crisis. Bulletin of the American Museum of Natural History, 227: 1-95, figs. 1-64. [p. 73, fig. 53]
1995 Pernopecten yini Newell & Boyd, 1995
N. D. Newell & D. W. Boid, 1955, figure 53.
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«DIAGNOSIS: Equilateral shells with length almost equal to height; small, symmetrical resilifer with resilial ridges; posterior auricular crus and marginal ridge longer than their anterior counterparts (table 22).
DISTRIBUTION: Leonardian-Wordian; AMNH loc. 369, 503, 509, 512; USNM loc. 702,703, 703a,703c, 706,706b,706c, 706e, 707e, 710d, 712a, 720d, 721j, 721s, 721u, 728, 738L.
DISCUSSION: The species is named after Yin Hongfu, the eminent student of Chinese Permian pectinoids. Our collection consists of 90 separated silicified valves –most of them fragments–from 19 West Texas localities. Our species is slightly more symmetrical than the Carboniferous members of the genus. Neither of its subequal auricles has a marginal sinus, although growth lines indicate that one was present beneath the anterior auricle ofjuvenile right valves. The West Texas form lacks several features that characterize the Carboniferous species as described by Newell (1937). These characters are: retrocrescentic outline and comb-like ridges on each side of RV resilifer. Girty's P. obliquus, 1908, from the Capitan Ls., poorly characterized, is more slender (see Newell, 1937: 113).» NORMAN DENNIS NEWELL & DONALD WILKIN BOYD, 1995
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