Trochidae
Calliostoma akoya (Kuroda in Ikebe, 1942)
Description
Pearly cream, fine spiral ribs, thin and color of the soft part
can be seen from the outside.
Locality
Japan: Off Choshi, Mouth of Tokyo Bay in 250m-300m, Sagami Bay in 300m
sandy muddy bottoms, Off Kii Peninsula in 200m.
Original articles of scientific name
1942 Kuroda in Ikebe JAP. JOUR. GEOL. GEOGR., vol. 18(4), pp.249-282,
pls.26-28, textfigs. 1-7.
Original of Japanese name
1934 Shintaro Hirase 'A collection of Japanese shells with illustrations
in natural colors'. Matsumura Sanshodo, Tokyo.
Remarks
Most of the pearly Trochidae, such as Bathybembix argenteonitens are
covered with thin periostracum. However, Calliostoma akoya does
not have periostracum.