La famille des Cicerinidae (Turbellaria, Kalyptorhynchia)

Abstract

The present study deals with 12 species of Cicerinidae. Further details are given for 6 species previously described: Toia ycia Marcus, Cicerina eucentrota Ax, Nan-norhynchides vividus Brunet, JV. harparius Brunet, N. corneus Brunet, Didiadema picardi Brunet. Two new species are described, Toia calceformis sp.n., different from T. ycia by half-boot shape of the cirrus, and Paracicerina globulosa sp.n., characterized by very short (4 μm) cuticular spermatic ducts and a spherical copulatory bulb provided with a spiny cirrus (35–40 μm long). Histological studies of Ptyalorhynchus coecus Ax confirm the generic separation of Ptyalorhynchus and Paracicerina; the main difference is the glandular girdle structure of the proboscis in Ptyalorhynchus which is split into two areas (inner and outer one) by basal circular muscles; the intensively stained secretion of the inner area is localized in 15 membranous canals. Pocillorhynchus gen.n., with two species, P. agilis sp.n. and P. minutus sp.n., is closely related to the genera Toia and Nannorhynchides, but differs from them by the following characters: proboscis with broad glandular girdle, devoid of circular muscle bulb, cuticular spermatic ducts long and thin (95–125 μm). From the comparison of their morphological and anatomical features, two groups of genera are distinguished in Cicerinidae; first group including Toia - Nannorhynchides - Pocillorhynchus, second group including Cicerina - Paracicerina - Etmorhynchus - Ptyalorhynchus - Zonorhynchus - Xenocicerina - Didiadema. Special attention is paid to proboscis structure. The study ends with an identification key for all known Cicerinidae.