Placopecten setanaensis (Kubota, 1950)
KUBOTA, K. 1950. A new species of Pecten (Placopecten) from the Neogene of Southwestern Hokkaido, Japan. Mineralogy and Geology, 3 (5): 133-135, pI. 7. [p. 184, pl. 7, figs. 1-4]
1950 Pecten (Placopecten) setanaensis Kubota, 1950
«In Japan as stated in earlier lines, only two fossil species, setanaensis and nomurai are considered to belong to Placopecten (pI. 31.). P. nomurai resembles P. setanaensis and its variation of measured characters is harmonious with that of setanaensis except for apical angle (Text-figs. 46, 47 and 48). Left valve of setanaensis is also more convex than right one (Text-fig. 46).»
SATO, Y. 1991. Paleontological study of molluscan assemblages of the Miocene Moniwa Formation, Northeast Japan and description of their Pectinidae. Report, Geological Survey of Japan, 272: 1-249, pls. 1-34. [p. 88, 91]
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Placopecten setanaensis (Kubota); Y. Sato, 1991, Paleontological study of molluscan assemblages of the Miocene Moniwa Formation, plate 29, figures 1-10.
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«Pecten (Placopecten) setanaensis Kubota, 1950b, p. 184, pI. 7, figs. 1-4; Kubota, 1950c, p. 95, pI. 9, fig. 63.
Holotype: – UH, Reg. No. 13549. Remarks: – This species differs from Placopecten clintonius (Say) (Op. cit.) by its more or less posteriorly contorted shell, very low, broad radial ribs which bifurcate towards ventral margin, interspaces between radial ribs with no intercalary threads and smaller auricles in which anterior one furnished with rather conspicuous byssal notch. Placopecten protomollitus (Nomura) is also distinguishable from the present one by its smaller shell, the right valve having more or less imbricated intercalary threads, the left valve having finely imbricated radial ribs and intercalary threads, and the smooth interior surface. From the morphological characteristics it is considered that the present species may be an active swimmer. Type locality, Geological formation and Age: – Left cliff at Kaigara-bashi, upper course of the Meppu River, Imagane-machi, Setana-gun, Shiribeshi Province, Hokkaido (Lat. 42°26'35"N., Long. 140°04'20''E.). Imagane formation. Early Miocene. Distribution: – Known only from the type locality and its vicinity. Occurrence: – Very abundant in the coarse-grained sandstone at the type locality and its vicinity.» MASUDA, K. 1962. Tertiary Pectinidae of Japan. Science Reports of the Tohoku University [2nd. Series - Geology], 33 (2): 117-238, pls. 18-27. [p. 194]
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Placopecten (s. s.) setanaensis (Kubota); K. Masuda, 1962, Tertiary Pectinidae of Japan, plate 23, figure 5.
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