|The anatomy of Cylindrotis quadrasi from Okinawa Island, Japan and the subfamilial position of the genus Cylindrotis Möllendorff, 1895 (Archaeopulmonata: Ellobiidae)|Fukuda, H. (1994). The anatomy of Cylindrotis quadrasi from Okinawa Island, Japan and the subfamilial position of the genus Cylindrotis Möllendorff, 1895 (Archaeopulmonata: Ellobiidae). J. Moll. Stud. 60(1): 69-81. hdl.handle.net/10.1093/mollus/60.1.69
In: Journal of Molluscan Studies. Oxford University Press: Reading. ISSN 0260-1230, more
Brackish water; Fresh water; Terrestrial
Cylindrotis quadrasi Mollendorff, 1895, the type species of the ellobiid genus Cylindrotis, was collected from Okinawa Island, southwest Japan. This is the first record of C. quadrasi in Japan and the third in the world. The anatomical characters of this species, i.e. shell, head-foot, pallial cavity, radula, stomach, reproductive system, and central nervous system, are described in detail for the first time. The significance of these observations is discussed and the subfamilial position of Cylindrotis is reconsidered. Cylindrotis was included in the Pythiinae, the most primitive group of the Ellobiidae, based on the conchological characters alone. However, the male and female tracts of the reproductive system are entirely separated, and other internal organs exhibit highly derived conditions. Accordingly, Cylindrotis is transferred from the Pythiinae to the Ellobiinae. Among the genera of the latter subfamily, Cylindrotis seems to be allied to Blauneria Shuttleworth, 1854 and Lcucophytia Winckworth, 1949.