Dr. Éva Murai szerk.: Miscellanea Zoologica Hungarica 3. 1985 (Budapest, 1985)

Györe, K.: Three ostracod species from Lake Velence new to the fauna of Hungary

Three ostracod species from Lake Velence new to the fauna of Hungary By K. GYÖRE (Received 14 November, 1984) ABSTRACT. Three ostracod species new to the Hungarian fauna: Candona holz- kampfi Hartwig, 1900, Physocypria fadeewi Dubowsky, 1926 and Potamocypris variegata Brady & Norman, 1889 are reported from Lake Velence. Hydrobiological analyses of Lake Velence were carried out between 1975 and 1979 on behalf of the Water Management Scientific Research Institute, Budapest. The ostracod species have been identified in the collected samples. In the course of processing the collected material three species have been found which had previously been unknown in the fauna of Hungary. FARKAS (1958), taking into account the ostracod fauna of the surrounding areas, mentioned the possibility of their occurrence. Only a few samples contained some individuals of Candona holzkampfi Hartwig, 1900, but specimens of Physocypria fadeewi Dubowsky, 1926 and Potamocypris variegata Brady & Norman, 1889 were found in every sample. Candona holzkampfi Hartwig, 1900 (Podocopa - Cypridacea - Candonidae - Candoninae) HARTWIG, 1900: 149; DADAY, 1903: 84, Tab. VI. figs 34-54; VAVRA, 1909: 95, fig. 386; MÜLLER, 1912: 138; DUBOWSKY, 1925: 269; KLIE, 1926: 37-53; KLIE, 1938: 62, figs 197- 198; BRONSTEIN, 1947:243, fig. 147; FARKAS, 1958: 56, fig. 60; NÜCHTERLEIN, 1969: 245. Synonyms: Eucandona csikii var. pannonica Daday, 1903; Candona fabaeformis Fischer, 1851 (NÜCHTERLEIN, 1969). Some individuals of the species were found in the sample collected from the soft bottom under a Schoenoplectus littoralis stand near the village Velence (16. 05. 1976). In the taxonomic keys I found that only the male individuals can be distinguished from Candona fabae formis Fischer. Although only few specimens could be studied I found that the females of the two species can also be clearly distinguished from each other on the basis of their valves. Valves of the females of C. holzkampfi are chopped on the back side from lateral view, more exactly the posterior margin is straight, while in C. fabaeformis they are rounded (Fig. 2c, d). The valve is 0.96 mm long (literature data mention 0.98 mm), its greatest height may be seen in its posterior third, being somewhat less than half of its total length (0.44 mm). Seen from above, the right and left bend of the edge contour are of the same shape, with its greatest width being in the back third. The dorsal margin of the left valve of the male is arched and that of the right valve is straight, and forms an angle with the frontal and the back edge (Fig. 2a, b). The ventral side *On the basis of the classification of HARTMANN & PURI (19 74).