Trichodinid ectoparasites (Ciliophora: Peritrichida) from the gills of cultured marine fishes in China, with the description of Trichodinella lomi n. sp.

Three species of cultured percoids, each heavily infested by trichodinid ectoparasites, were examined from over-wintering pools in Qingdao, China during the winter of 1995. A total of five species of trichodinids belonging to three genera, Trichodinella Sramek-Husek, 1953, Dipartiella Shtein, 1961 and Trichodina Ehrenberg, 1838 were recorded. One new species, Trichodinella lomi n. sp., is described, the denticle of which is characterised by its acutely triangular blade, comma-like central part and inconspicuous ray. The morphology of Trichodina murmanica Poljansky, 1955 was re-investigated. Three other little-known species are redescribed: Dipartiella simplex (Raabe, 1959) Shtein, 1961, Trichodina japonica Imai, Miyazaki & Nomura, 1991 and T. domerguei (Wallengren, 1897).