(Oyama in Kuroda, 1951)
|Original name||Ctenamusium (Micramussium) siratama Oyama in Kuroda, 1951|
|Autoreference||Oyama in Kuroda, 1951: 80, pl. 13, figs 5-7.|
|Reference||Oyama, K., 1951. Amusiinae in Japan. In: T. Kuroda (ed.), Illustrated catalogue of Japanese shells 13: 79-89.|
|Type data||Figured holotype (pr: H 7.4 mm, L 7.5 mm, D 2.8 mm). Type material probable in private collection of Dr K. Oyama at Toba. Type locality: Japan, Sagami Sea, off Manazuruzaki, 234-291 m.|
Shell up to ca. 12 mm high, semi-transparent, weakly inflated, circular, left valve slightly more convex than right valve, nearly equivalve, equilateral, auricles smooth and nearly equal in size, colour left valve usually pale-brownish or whitish, right valve creamy or whitish.
Left valve with irregularly spaced, delicate radial lirae in early growth stage to the central part of the disc, with very fine commarginal lamellae.
Right valve with regularly spaced commarginal lirae. Internal ribs 9-10, sometimes with a rudimentary intercostal riblet. Byssal notch and ctenolium lacking.
Japan (TL), Philippines, Indonesia, New Caledonia
|Habitat||Living bathyally on soft bottom assemblages.|