Maclearnia mimikirensis (Kurata & Kimura in Kimura, 1951)
KIMURA, T. 1951. Some pectinids and a limid from the Jurassic Torinosu group in Japan. Journal of the Faculty of Science, University of Tokyo [Section II: Geology, Mineralogy, Geography, Seismology], 7 (6-10): 337-350, pI. 1 [p. 341, pl. 1, fig. 13]
1951 Camptonectes (?) mimikirensis Kurata & Kimura in Kimura, 1951
T. Kimura, 1951, plate 1.
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«Camptonectes (?) mimikirensis KURATA and KIMURA, n. sp.
PI. I, Fig. 13. Description:— Valve a little convex, longer than high; the outline exclusive of the ears fan-shaped, triangular on the dorsal and semicircular on the ventral side; beak not prominent but wide; ears not well preserved; posterior ear smooth, rather small, probably truncated behind obliquely; anterior ear probably much larger, its anterior part being broken off; furrows below the ears a little deeper on the anterior than the posterior side.
Surface marked with numerous, quite regular and concentric striae which are very narrow and rounded on the top. They are bent up abruptly near the lateral margin where they become narrower and more crowded. The above description is based on the type right valve. Dimension:— The holotype (No. 7100) is 40.5 mm in height and 43.7 mm in length and its umbonal angle 102 degrees. Comparison:— In another specimen (No. 7101) which is, though much higher than long, probably caused by secondary deformation, is thought to belong to this species. A triangular resilifer is seen delimited by a prominent ridge on each side. The ears are incomplete, byssal sinus not well observed and "Camptonectes striation" also can not be seen, although the concentric ornamentation rather well preserved, but because the furrow below the anterior ear is a little deeper than the posterior, its reference to Camptonectes may be warranted. This species is closely allied to Pecten jamoigensis TERQUEM and PIETTE (1868, p. 104, pI. 12, figs. 20, 21). The latter has faint radial striae, apparent byssal sinus, and more delicate concentric lines than the former. This is also quite similar to Pecten (Entolium) erraticus FIEBELKORN (1893, p. 400, pI. 14, fig. 12), but the outline is broader and concentric striae more numerous in the former than in the latter. Occurrence:— Mimikire.» NOBUO KURATA & TOSHIO KIMURA, 1951
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