Dr. Éva Murai szerk.: Miscellanea Zoologica Hungarica 4. 1987 (Budapest, 1987)
Murai, É.: Triodontolepis torrentis sp. n. (Cestoda: Hymenolepididae) a parasite of Neomys fodiens (Insectivora)
DISCU SSION YAMAGUTI (1959) gave the shape of the hooks as the most important character in the diagnosis of the genus Triodontolepis: "Rostellar hooks 10 or more, Y-shaped in profile: guard bifurcate, nearly as long as, or longer than blade; handle as long as, or longer than blade'.' PROKOPIC (1972, p. 283) amended this description by his following observations: ". . . we observed on the hooks of members of the genus Triodontolepis that the guard is not bifurcated and that bifurcation is mimicked by a thickening of both sides of the guard which, however, are connected by a distally undulated membrane. Through this thickening a groove of varying depth is formed in the centre of guard. " The shape of the hooks of Hymenolepis bifur ca (Hamann, 1891) - bifurca-type - is wellknown in the literature. According to PROKOPIC (1972) the "bifurcate" adjective does not necessarily mean that the tip of the guard branches into two. I have observed, however, that there is a notch of variable depth on the tip of the guard-lobe (Figs 2, 10- 11, 17, 23, 24, 29). The shape of the hooks of T. bifurca, T. hamanni , T. neomidis, T. skrjabini, T. sumavensis (a probable synonym of T, bifurca), T. kurashvilii, T. rysavyi and the new species T. tor rentis sp. n. is all in accordance with this finding. PROKOPlC (1972) proposed that the description of the genus be amended by the critérium that in the uterus "the presence of capsule-shaped formations covering the eggs" is a generic feature of the genus. PROKOPIC also noted that this feature, the formation of "egg cocon" after SPASSKY and ANDREJKO (1969) is also found in other hymenolepidid genera, e. g. in Coronacanthus and Insectivorolepis. The genus is homogeneous as regards the shape of the hooks, the new species differs from the others as regards the formation of egg cocons, as T. torrentis sp.n. does not form egg capsules, the mature eggs are freely distributed in the uterus of the gravid segment (Fig. 28). The Triodontolepis species are generally small (adults measure 8-20 mm x 0. 3-0.4 mm in various host species), the shape and the size of the scolex are very similar and since several species may coexist in a given host, it is very difficult to separate the various species. The onion-shaped scoleces of Triodontolepis may be distinguished from the sympatric bowl-shaped scoleces of the Coronacanthus species. In a single host (Neomys fodiens , Chy2né, No. 3086/25017) among the 40 mounted specimens there were 15 T. torrentis sp.n., 16 T. hamanni , 1 T. skrjabini, 6 T. bifurca and 2 Coronacanthus integrus (Hamann, 1891). The features of the species, the size of their organs and the shape and size of the egg cocons are very similar. Members of the T. bifurca group have wider and stronger scoleces and rostella which are visible even with the aid of low magnification of stereo microscope. T. tor rentis sp.n. may be recognized by the freely distributed mature eggs in the last segments. Useful characters for identifying Triodontolepis species are the number and size of the hooks and the slighter morphological differences among the various species. There may be slight variation in the number of hooks among the various species: e. g. in T. sumavensis of the T. bifurca species group there are 12 hooks instead of 10, among the T. skrjabini specimens examined by me there was one with 11 hooks instead of 10, and the number of hooks in T. hamanni varied between 16 and 20 (with one case of 21). It is worth taking into consideration the total length and the lengths of the basis (from the tip of the handle to the outer edge of the guard), the handle, the blade, and the width of the lobe of the guard and the depth of the notch in the middle of the lamella of the guard. On the basis of this it is possible to separate e.g. the hooks of T. hamanni from those of T. skrjabini: T. hamanni T. skrjabini No. of hooks 16-20 10(11) Total length 27-30 jam 25-26 (27) jim Basis 25-27 jam 22-25 (27) jam Width of guard-lobe 5.5-5. 6 ^um 8-lO^m Bifurcation 3 jam 6, um Of the species closely allied to T. hamanni, PROKOPIC and MATSABERIDZE (1971) characterized T. kurashvilii by hooks with strikingly short handle and PROKOPIC (1972) described T. rysavyi as having unusually long handle.
