Vertipecten yneziana subyneziana (Weaver & Kleinpell, 1963)
WEAVER, D. W. & R. M. KLEINPELL. 1963. Mollusca from the Turritella variata Zone, in Kleinpell, R. M., and Weaver, D. W., Oligocene biostratigraphy of the Santa Barbara Embayment, California. University of California Publications, Bulletin of the Department of Geological Sciences, 43 (2-3): 81-250, pls. 18-38. [p. 198, pl. 31, figs. 2, 3, 7]
1963 Pecten (Vertipecten) yneziana subyneziana Weaver & Kleinpell, 1963
«This form is all but indistinguishable from P. yneziana yneziana except for its much smaller size. Young forms of P. yneziana yneziana are not available for comparison. However, where known to date, the two morphological varieties seem to occupy separate stratigraphic intervals in the column.»
DONALD W. WEAVER & ROBERT MINSSEN KLEINPELL, 1963
[Original description from E. J. Moore, 1984] |
«Comparative morphology [Vertipecten yneziana (Arnold, 1907)]. Adults are smaller, fewer ribbed than those of V. perrini. Umbonal angle smaller than in V. perrini, greater than in V. alexclarki. The types of Pecten (Vertipecten) yneziana subyneziana Weaver and Kleinpell (1963) are internal molds of small right valves having 20 or more ribs, but they are not well enough preserved to identify with certainty (pl. 38, fig. 5).»
SMITH, J. T. 1991. Cenozoic Giant Pectinids from California and the Tertiary Caribbean Province: Lyropecten, "Macrochlamis", Vertipecten, and Nodipecten species. United States Geological Survey Professional Paper, 1391: v + 1-155, figs. 1-18, pls. 1-38. [p. 86]
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Pecten yneziana subyneziana Weaver and Kleinpell; J. T. Smith, 1991, Cenozoic Giant Pectinids from California and the Tertiary Caribbean Province, plate 38, figure 5.
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«Holotype.— C AS/SU 9265.
Type Locality.— UC 86940. Santa Barbara County, Calif. Coldwater Sandstone, Eocene. Supplementary description.— "With this previously undescribed subspecies the very phylogenetic radicle of the subgenus Vertipecten, as described by Grant and Gale (1931, pp. 188-189), is now recognized. In fact, one faces the problem of whether to classify this 'connecting link' with its immediate ancestors of Chlamys, as its small size alone would seem to dictate, or with its larger and more robust descendants of Vertipecten, from which it is all but indistinguishable except for the very small size." (Weaver and Kleinpell, 1963, p. 198) Geographic range.— Southern California. Geologic range.— Eocene to Oligocene. Occurrence in California.— Eocene: Coldwater Sandstone; Eocene and Oligocene: Sacate and Gaviota Formations undifferentiated (Weaver and Kleinpell, 1963).» 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. B61]
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Vertipecten yneziana subyneziana (Weaver and Kleinpell); E. J. Moore, 1984, Tertiary Marine Pelecypods of California, plate 24, figure 3.
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«Weaver and Kleinpell (1963, p. 197) identified Pecten (Chlamys) sespeensis Arnold, a Vaqueros species, in both the so-called Coldwater Sandstone (late? Eocene) and the upper part of their Gaviota Formation (? horizon middle Oligocene) of southern California. One of the specimens they figured (pl. 29, fig. 10, pl. 30, fig. 1) from the Gaviota Formation is very close to the boundary between Chlamys and Vertipecten, morphologically. Weaver and Kleinpell (1963, p. 198) also recorded Vertipecten yneziana (Arnold) from early (?) to late Oligocene beds in the same region. This is certainly a Vertipecten, and I see no reason to doubt the specific identification.
At the same time, Weaver and Kleinpell (1963, p, 198, pl. 31, figs. 2, 3, 7) described a new subspecies, Pecten (Vertipecten) yneziana subyneziana which they recorded from both the so-called Coldwater Sandstone (late? Eocene) and the undifferentiated Sacate-Gaviota Formation (late Eocene or early Oligocene). They say, "With this previously undescribed subspecies the very phylogenetic radicle of the subgenus Vertipecten, as described by Grant and Gale (1931, p. 188-189), is now recognized." Unless Vertipecten as presently construed is polyphyletic, I am inclined to doubt this conclusion. Assuming the age assigned to this subspecies is correct, it does not conform morphologically to what I would expect the prototype species of Vertipecten to be. It is possible, of course, that Vertipecten is polyphyletic and that finely ribbed species such as V. porterensis (Weaver) and coarsely ribbed species such as V. fucanus (Dall) belong to different genera.» MACNEIL, F. S. 1967. Cenozoic pectinids of Alaska, Iceland, and other nothern regions. United States Geological Survey Professional Paper, 553: iv + 1-57, pls. 1-25. [p. 38]
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