Dr. Fűköh Levente szerk.: Malakológiai Tájékoztató 12. (Eger, 1993.)

MIENIS, H. K.: A note on the systematics and distributionof „Cocculina" simplicior Melvill, 1912 (Mollusca, Gastropoda, Lepetellidae)

A note on the systematics and distribution of „Cocculina" simplicior Melvill, 1912 (Mollusca, Gastropoda, Lepetellidae) H. K. Mienis Abstract: Cocculina simplicior Melvill, 1912, described originally from the Gulf of Oman, is reported from dredgings carried out in the Gulf of Aqaba. On conchological characters the species is transferred from the genus Cocculina Dall, 1882, Fam Cocculinidae, to the genus Lepetella Verrill, 1880. Fam. Lepetellidae. Key words: Gastropoda, Cocculina simplicior, Lepetella, systematics, distribution. Introduction Between 1892 and 1914 Frederick W. Townsend carried out intensive dredging activities in the Arabian Gulf (formerly Persian Gulf), Gulf of Oman and northern Arabian Sea, while working as chief of the Telegraph Staff aboard the Indian Government Steamer „Patrick Stewart" of the Indo-European Telegraph Company. The first samples of molluscs among this material were studied by G. B. Sowerby (1894— 1895), whose papers were followed by numerous studies of Melvill and Melvill and Standen (see Trew, 1987, for a complete list of those papers and the new taxa they contain). Most papers by Melvill (and Standen) are devoted to the description of new taxa. Many of the new (sub)species, especially those from deepwater, remained known sofar from the typelocality only. This is also the case with Cocculina simplicior Melvill, 1912, a tiny saddle-shaped gastropod dredged in the Gulf of Oman. Although Franc (1956: 25) mentioned Cocculina simplicior from North Cape of Abulat Island, Red Sea, the specimens in question turned out to be misidentified and belong in reality to a species of the genus Patelloida Quoy & Gaimard, 1834, Fam. Acmaeidae (the late Dr. I. Yaron in litt.). Never-the-less the species seems to live in the Red Sea because dredgings carried out in the northern part of the Gulf of Aqaba have resulted in the discovery of several shells, wich agree in full detail with the description and figure of Cocculina simplicior. A study of the shell characters has revealed that it has nothing in common with either Cocculina Dall, 1882, or any other genus of the family Cocculinidae. In fact there exists a striking resemblance between Cocculina simplicior and Lepetella laterocompressa (De Rayneval & Ponzi, 1854), an Atlantic-Mediterranean species (Warén, A. 1972; Panetta, P. 1973; Mienis, H. K. 1981). Cocculina simplicior in therefore transferred to the genus Lepetella Verrill, 1880, of the family Lepetellidae.