L. Forró szerk.: Miscellanea Zoologica Hungarica 8. 1993 (Budapest, 1993)
Biserkov, V. Y., Mészáros, F. , Genov, T.; Chipev, N.: The synlophe of Dessetia moldovensis (Andreiko, 1963) (Trichostrongyloidea, Heligmosomidae), from the lesser mole rat, Spalax leucodon Nordmann, (Rodentia, Spalacidae)
6 V. Y Biserkov, F. Mészáros, T. Genov and N. Chipev Description of synlophe Description of the synlophe of Bulgarian specimens The ridges begin immediately behind the head vesicle and disappear before the bursa of males and before the anus of females (Figs 1,2). Number of ridges varies depending on position of transverse section. Maximum number of ridges in both sexes is 16, but they may be observed only before the vulva and the bursa respectively, where all ridges are with similar dimensions. In both sexes two ridges appear immediately after the head vesicle: one ventral and one left ventrolateral ridge (Fig. IB). At the level of the posterior part of oesophagus there are 8 ridges (Figs 1C,D,E; 2C,D). At the level of the anterior part of intestine it both sexes the degree of inclination of the orientation axis of ridges is about 50° and their number is 11 (Figs. 1F,G; 2E,F). In the middle of the body the angle of the orientation axis of the synlophe is about 70°; number of ridges decreases to 9 (Figs 1H; 2G,H). In females number of ridges increases up to 16 in the area before vulva (Fig. 3L); when the number of ridges becomes 12, their dimensions are almost equal with 4 ventral left ridges remaining somewhat bigger which correspond to the ventral left comaretes and their neighbour ridges. In males the number of ridges in the area before the bursa increases up to 16, as in females, but in contrast the ventral right lateral surface in males has no ridges (Fig. 1J,K). Notes on the synlophe of Hungarian specimens (Fig. 4) The synlophe of Hungarian specimens is similar to that of Bulgarian specimens. There are some differences in the relative dimensions of the comaretes with respect to the body width. The comaretes of Hungarian specimens are somewhat bigger. Notes on the general morphology of the species The description of the species presented by Genov & Yanchev (1981) and Genov (1984) corresponds completely to the material studied by us with the exception of the shape of the head vesicle, the end of spicules and vulval valve (Fig. 5). Spicules have lateral alae at the distal end (Fig. 5B, C). The vulval valve is massive and its anterior part appears as a ventral thickening of the body, while its posterior part is hanging over the vulva. The form of the valve presented in Genov & Yanchev (1981) and Genov (1984) seems to be the result of a strong compression of the body of the studied specimens. Discussion The angle of the orientation axis of the synlophe of Dessetia moldovensis with respect to the sagittal axis is about 64° in the middle of the body and corresponds to the orientation presented by Durette-Desset (1983) for this species and used in the system of the Trichostrongyloidea. In the description of the synlophe of D. moldovensis by Genov & Yanchev (1981) and Genov (1984) lateral chords were not mentioned and the orientation used by them remains uncertain. The maximum number of ridges in these first descriptions were not discussed, but they were
