Cochlostoma mienisi of southwestern Turkey: Its distribution range and conchological characterization

A survey was carried out to determine the distribution range of Cochlostoma mienisi Schütt, 1978, a little studied land snail of southwestern Turkey. The species was found on the island of Kekova off the coast of Turkey and at an additional location on the mainland facing the island. The closest congeners of C. mienisi are on Crete and mainland Greece, more than 400 km away. As a possible explanation for its limited and disjunct range, it is proposed here that C. mienisi may have been introduced from another location by the shipping trade in the antiquity. No live snails were seen, but various conchological traits of C. mienisi provided clues to its biology and ecology. The presence of two overlapping size groups in the distribution of adult shell dimensions is interpreted as an indication of a sexual dimorphism: the larger shells (8.0 mm × 3.5 mm) are those of female snails and the smaller ones (7.4 mm × 3.3 mm) are of males. Also discussed are the structure of the operculum of C. mienisi, decollation observed in a few shells and the presence of small circular holes that were probably bored by an unknown predator or a parasite.