Studies on the ectocommensal ciliate, Trachelostyla tani nov. spec. (Protozoa: Ciliophora: Hypotrichida) from the mantle cavity of the scallop Chlamys farrei

Abstract

The morphology and infraciliature of the marine ectocommensal ciliate, Trachelostyla tani spec. nov., isolated from the mantle cavity of the scallop Chlamys farrei in the coastal water off Qingdao, China, were studied using protargol staining method. Diagnosis for the new species: highly spiral and flexible marine Trachelostyla with pointed anterior and posterior ends, in vivo 135–210×25–35 μm; about 80 adoral membranelles, 13 frontoventral and 5 transverse cirri; marginal cirral row spirally arranged, posteriorly influent; two dorsal kineties with 2 caudal cirri at posterior extremity; constantly 2 macronuclei. Based on the data obtained, an improved definition for the genus Trachelostyla is suggested: Oxytrichids with lanceolate or spindle-like body shape, usually flexible and more or less spirally twisted; frontoventral cirri variable in number and mostly confined to narrowed frontal region, 5 transverse cirri; one marginal row on each side, caudal cirri present; mostly as ectocommensal or benthic form in marine biotopes, gelatinous lorica commonly present.