Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 90. (Budapest 1998)

Hír, J.: Cricetids (Rodentia, Mammalia) of the Early Pleistocene vertebrate fauna of Somssich-hegy 2 (Southern Hungary, Villány Mountains)

M3 (Fig. 28, Table 3). The morphology of this molar is rather variable. In the dis­persion of the different types we could not find unambiguous tendencies. ml (Fig. 29, Table 4). The "morphotype-spectrum" of the recent and Villány 8 ma­terials are unimodal, because the frequencies of the dominant morphotypes are very high. In the Solymár and Somssich-hegy 2 samples the importance of dominant and subdomi­nant types is stronger. The morphology of the Recent material is the most reduced and most homogeneous. The material of Somssich-hegy 2 is the most variable. m2 (Figs 30-3 1, Table 5). The morphology of this molar is very variable. The mor­photypes from the recent and the Villány 8 materials give a morphodynamic scheme demonstrating a trend of simplification. This process begins with morphotypes bearing a central ring and mesolophid. During the course of phylogeny the central ring is split and the mesolophid is shortened. Finally both of these elements disappear. But the direct application of this scheme is impossible in the other two materials. The frequency of the "extra types" (different from the Recent-Villány 8 types) is 12% in Somssich-hegy 2, but 47% is in Solymár. The common feature of these morphotypes is the presence of an extra morphological element: the "paramesolophid" (Fig. 31). By the side of the normal MSLD another enamel ridge develops starting from the hypolophulid. or from the joining point of the ectolophid and the hypolophulid. This element is not named in the nomenclature of MEIN & FREUDENTHAL (1971a, b). On the basis of the evolutionary trends the Villány8-Recent and Somssich-hegy 2­Solymár pairs strongly differ. In the V8-Recent line the morphology simplified but in the Somssich-Solymár line the morphological variability is advanced. m3 (Fig. 32, Table 6). On the basis of the presence and the development of five ele­ments we could create an analytic morphotype system for the m3 molars. The morpho­logical characters of the m3 is very similar to the m2. In Villány 8 the central ring is more frequent than in the recent material. The "paramesolophid" and the ectomesolophid are found in the Somssich-hegy 2 and in the Solymár materials. The morphological variability is highest in Solymár and lo­west among the Recent species. Table 6. The distribution of the morphotypes of ihe m3 molars in the four investi gated Cricetus materials C. cried us C. praeglacialis C. runtonensis C. runtonensis solymarensis runtonensis recent Villány 8. Solymár Somssich-hegy 2 14000 7.7 54.6 ­35.0 1 3000 0.8 10.6 ­4.0 1 1000 ­10.6 ­5.4 04000 47.7 5.7 2.3 8.8 03000 0.8 1.3 2.3 4.7 05000 40.0 1.0 4.6 2.7 Annls hist.-mu. Mus nam. hung. 90, 1998

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