Szabó János szerk.: Fragmenta Mineralogica Et Palaentologica 23. 2005. (Budapest, 2005)

2 MESZOELY, VENU The centra of the trunk vertebrae assigned to Vipera (HNHM Gyn/409., Gyn/410., Gyn/420., Gyn/427.) are long and with depressed neural arches bearing a distinctly low and long neural spine. The hypapophyses are shorter than the centra and is hooked postero-ventrally. All of the vertebral characters listed are consistent with those of the "berus group" of the genus Vipera (SZYNDLAR 1984). The basiparasphenoid of Natrix (HNHM V.98.7.) is small and incomplete, measuring 3.5 mm. On its ventral surface the basisphenoid crest is broad and short in comparison with Coronella and Vipera. The pterygoid crests are well developed and directed posteroventrally and terminate in the pterygoid processes (Figure 3a). The Vidian canal is extremely short and its anterior opening is not accompanied by the "cid" nerve foramen. The latter character is regarded as a "modern" pattern for the species group (SZYNDLAR 1991b). On the dorsal surface the pituitary fossa is short and broad and has a somewhat squarish appearance. The parasphenoid portion is not preserved (Figure 3b). The vertebrae assigned to Coluber (HNHM Gyn/406., Gyn/414., Gyn/421., Gyn/424.) resemble closely that of Coluber caspius, described and figured by SZYNDLAR (1991a) from Yarbesh, Bulgaria. In lateral view the neural arch of the trunk vertebrae is vaulted and provided with a high and long neural spine, slightly overhanging anteriorly and posteriorly. The dorsal margin of the neural spine is not keeled. The parapophysis is slightly longer than the ZEL. & GASPARJK diapophysis. In ventral view the haemal keel is prominent with a thin ventral margin. In dorsal view the zygosphene is concave or slightly crenate; the prezygapophyseal processes are long about the same length as the prezygapophysis and distally pointed. In 12 measured vertebrae the centrum length ranged between 5.51—7.75 mm. The centrum length/centrum width ratio was 1.18— 1.36 (mean = 1.27). The three basiparasphenoid from Tokod have been compared with recent species housed at the Herpetology Department of Harvard Museum of Comparative Zoology and at the Hungarian Natural History Museum and the Tarii Crisurilor Museum in Oradea, Romania. There is good agreement in general morphology between the Tokod fossils and the basiparasphenoids of recent genera of Coronella, Vipera, Natrix and Coluber. However it must be emphasized that the Tokod material is too limited and fragmentary to allow for definitive specific assignment. Table 1 — Numbers of vertebrae of the four snake taxa from the different layers of Tokod II locality. layers: 1-2 3 4 5 Coronella sp. 15 8 12 28 Coluber sp. 20 31 45 11 Natrix sp. 2 2 20 15 Vipera sp. 90 75 95 42 Figure 1 — Coronella sp. (HNHM V.98.8.) basiparasphenoid from the layer 4 of Tokod II locality. — a = ventral view; b = dorsal view.