L. Forró szerk.: Miscellanea Zoologica Hungarica 9. 1994 (Budapest, 1994)

Nesemann, H.; Neubert, E.: New data to the leeches of the subfamily Trochetinae (Hirudinea, Erpobdellidae)

sometimes reduced (Archaeobdella esnionti). Occurs in fresh or brackish waters of the Palaearctic region. The highest diversity is found in the Western Palaearctic area and the tributaries of the Black Sea. Description of taxa found in West Mediterranean freshwaters Trocheta subviridis Dutrochet, 1817 1817 Trocheta subviridis Dutrochet, Bull. Sei. Soc. philomat.: 130. This species is relatively unknown and often confused with other species of the genus. For this reason, a diagnosis for T. subviridis is given. The description is based on new material from the collection of the authors. The species is distributed in northern Italy, France, Luxemburg, Southern England, and Ireland. Material: France, Pyrenees at Fabian, catchment area of the Garonne, August 1989, leg. M. Hauser [1 specimen, preserved in formoll. England, small stream at Reading Berks, 18. 1. 1960, leg. K. H. Mann [6 specimens, ex coll. Hungarian Natural History Museum Budapest, preserved in etanol]. Description: Medium-sized to large leeches up to 140 mm length and a medium width of 15 mm; dorsally flattened, lateral fringes less prominent (Fig. 1). Annulation: somites with 8-11 annuli, annulus b6 in adult specimens always widened and heteronomously subdivided into three annuli of the same width. Annulation formula of the postclitellar somites bl, b2, b2 (c3, c4), a.2 (b3, b4), b5 (c9, cIO), ell, d23, d24 (Figs 5, 6). Dorsal part of the cranial sucker elongated. Paragnaths large and elongated, but more slender than in other species of the genus Trocheta (Figs 4, 7). Dorsal colour brownish with one pair of paramedian longitudinal stripes, lacking any papillae, spots or lines (Figs 1, 6); ventrally uniformously grey. Genital pores separated by 6 - 9 annuli, male porus in the furrow XII c2/c3 (or XT! c2/b2), female porus in Xll/Xni (XII d24/Xm cl) (Fig. 5); sometimes shifted caudad on XIII cl. Atrium medium sized with short coiled cornua. The cornua reach somite XI (Figs 2, 3, 8, 9). Trocheta subviridis can always be recognized by the large distance between its genital pores (Fig. 5). Figs 7-9. T. subviridis, England, small stream Reading Berks, 18. 1. 1960, leg. K. H. Mann; 7 = Cranial sucker with pharynx and paragnaths, ventral view; 8 = Atrium, ventral; 9 = Atrium, lateral