Praespondylopecten Romanov, 1987
KASUM-ZADE, A. A. & L. F. ROMANOV. 1987. Spondylopectinidae Kasum-Zade & Romanov, fam. nov. of Jurassic in the south of the USSR. In: L. A. Nevasskaya (Ed.), Stratigraphy of the Moldavian Upper Phanerozoic. Shtiinstsa, Kishinev: 6-16, pl. 1, 2 (in Russian). [p. 13]
«Genus Praespondylopecten Romanov, gen. nov.
Type species. Praespondylopecten besnossowi sp. nov. M-8/230, IG AN SSR. Northern Caucasus, Lower Jurassic, Pliensbachian.
Diagnosis. Shell is small, rounded oval, inequivalved. Left valve is more convex. Hinge margin is straight. Apical angle is blunt. Auricles unequal: anterior is larger and with deep byssal notch. Hinge structures consist of two teeth, with one on each side of the resilifer on the right valve, and corresponding depressions {pits} on the left. Sculpture consists of radial ribs (up to 16), not identical on the valves. On the right, they are wider with interspaces narrower than the ribs; on the left, they are narrow and with interspaces wider than the ribs.
Species composition. Monotypic genus. Only one species is known from the Lower Jurassic of northern Caucasus. Pliensbachian stage.
Comparisons and comments. It is most closely related in shell morphology to the genera Pseudopecten Bayle, 1878 and Spondylopecten Roeder, 1882. With representatives of the genus Pseudopecten, the similarity appears in the outer elements of the shell. Differences consist in the presence on the hinge margin of the right valve of two large teeth, one on each side of the resilifer.»
LEONID FEDOROVICH ROMANOV, 1987
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Praespondylopecten besnossowi sp. nov.; A. A. Kasum-Zade & L. F. Romanov, 1987, Spondylopectinidae Kasum-Zade & Romanov, fam. nov. of Jurassic in the south of the USSR, plate 2, figures 10-12-
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