Boros István (szerk.): A Magyar Természettudományi Múzeum évkönyve 50. (Budapest 1958)

Soós, Á.: New data to the ecology and distribution in the Carpathian Basin of Trocheta Bykowskii Gedr. (Hirudinea)

New Data to the Ecology and Distribution in the Carpathian Basin of Trocheta Bykowskii Gedr. (Hirudinea) By A. Soós, Budapest Aside of the common medicinal leech, the largest leech of Europe, Trocheta Bykowskii Gedr., awoke the interest of research workers from especially two points of view in recent times. One of them is its characteristical amphibiotic habits and sporadic distribution, the other the annulation of its body segments. On this occasion, I wish to discuss but the former problem. As is well-known, the species T. Bykowskii was described by G e d r o y 6 (2, p. 32—36) in 1913, from Bubnistze on the northern slopes of the Eastern Carpathians. The nine specimens serving for his description were collected by him in a lime-bearing spring, that is, in its outflow in a deciduous forest. Afterwards, there were no further publications concerning this species for about 25 years, and it seemed that this too will belong to the Trocheta species which have •never again been collected since their description, as, for instance, Trocheta Horsti Blanch. 1897, T. quadrioculata Oka 1922, and T. quinqueannulata Lukin 1929. Pawlowski, the best authority on the European species, gives a newer analytical description of T. Bykowskii Gedr. in his comprehensive work on the leech fauna of Poland (4, p. 166—170), in 1936. Indeed, he detailedly discusses in a separate paper and in the same year (5), the external morphology and systematical position of T. Bykowskii Gedr. Namely, Gedroy c (3) erected a special genus called Blanchardia for this species, in 1916. Pawlowski (5, p. 347—348) expounds point by point in this paper that the establishing of the genus Blanchardia is not justified, replacing the species again into the genus Trocheta. In the above mentioned paper, Pawlowski publishes the same three collecting localities again from the northern side of the Northeastern Carpathians. In 1936, Pawlowski conducted further collectings in the rivulets and their springs on the northeastern slopes of the Czarnahora, where he succeeded to find more than 20 living specimens of this species. He kept these in an aquarium in his laboratory for months, studying mainly their movement habits and behaviour in captivity. The results of his observations and experiences were published in 1938 (6). Up to 1949, we do not hear anything about T. Bykowskii Gedr., justly considered up to that time an endemic species of the fauna of Poland. Then, in a short preliminary report of Pawlowski (7), we read two very interesting statements of his. First, his analyses on the segments of the living specimens of T. Bykowskii Gedr., led him to the conclusion that a portion of the specimens published under the name T. subviridis Dutr., is really identical with T. Bykowskii Gedr. For the justification of P a w 1 o w s k i's above statements, I can bring forth two data. Perret, in his paper discussed detailedly below, shew among others (8, p. 128, 135) that the specimen considered as T. subviridis Dutr., by André (1) from the canton of Genève is identical with T. Bykowskii Gedr. During the working out and reviding of the material of the Hungarian Natural History Museum I too have established now that the T. subviridis Dutr. specimen from Comitat Bars and published by me in 1939 (9, p. 46) is also T. Bykowskii Gedr. The other communication worthy of interest of P a w 1 o w s k i's above paper is that T. Bykowskii Gedr. was also found in Austria, namely, in the river Mur in Steiermark. As Pawlowski writes (7, p. 74), ,,this is the first time that T. Bykowskii Gedr., was found outside of the area of the Carpathians". We find the latest detailed information on this species in the work of P e r r e t (8, p. 127—137). He also thoroughly examined segmentation, but arrived at an interpretation of the annulation of segments contrarily to the opinions of Blanchard and Pawlowski. As I have already mentioned, I do