Vipera latastei, Bosca, 1878

Torres-Roig, Enric, Mitchell, Kieren J., Alcover, Josep Antoni, Martínez-Freiría, Fernando, Bailón, Salvador, Heiniger, Holly, Williams, Matthew, Cooper, Alan, Pons, Joan & Bover, Pere, 2021, Origin, extinction and ancient DNA of a new fossil insular viper: molecular clues of overseas immigration, Zoological Journal of the Linnean Society 192 : -

DIFFERENCES BETWEEN VIPERA LATASTEI LATASTEI AND VIPERA LATASTEI EBUSITANA

E i v i s s a n Vi p e r a l a t a s t e i e b u s i t a n a d i f f e r s morphologically from the Iberian V. latastei latastei in the following traits: the trunk vertebrae of the fossil present a smaller and more rounded cotyle and condyle ( Fig. 4F, G, K, L). The latter has a diameter similar or slightly smaller than the neural canal ( Fig. 4G, L). In V. l. latastei the cotyle and the condyle are subelliptical and the condyle has a larger diameter than that of the neural canal ( Fig. 4U, V). Anterior and posterior parts of the neural arch have a similar height in V. l. ebusitana ( Fig. 4H), whereas in V. l. latastei it is higher posteriorly ( Fig. 4W). The diapophyses of V. l. ebusitana are well developed and present a subspherical shape, whereas the parapophyses are indistinct from the parapophyseal process ( Fig. 4H, M). In V. l. latastei the diapophyses are elongated dorsoventrally and the parapophyses have a diffuse outline but are well defined ( Fig. 4W). The subcentral ridge is poorly developed in V. l. ebusitana ( Fig. 4H, M), whereas in V. l. latastei it is well marked ( Fig. 4W). The zygosphene is trilobulate in both taxa, but in V. l. ebusitana, the central lobule is similar or slightly longer than the lateral ones ( Fig. 4D, I), whereas in V. l. latastei the lateral lobules are more developed than the central one ( Fig. 4X). Similarly, V. l. ebusitana and V. l. latastei have short prezygapophyseal processes, but in the first these processes are generally more acute than in the second ( Fig. 4I, N, X). In V. l. ebusitana the articular facets of the zygantrum are extended posteriorly forming two small spines visible in the dorsal/ventral view of the vertebra ( Fig. 4N), whereas in V. l. latastei the zygantrum remains completely covered (hidden) by the neural arch ( Fig. 4X). The anterior branch of the pterygoid of V. l. ebusitana is proportionally shorter and wider than in V. l. latastei (length/width = 7.1 mm / 0.81 mm). Moreover, V. l. ebusitana presents a ratio teeth number/ length (7/3.52 = 1.99) higher than in V. l. latastei (ectopterygoid process located between the eighth and ninth teeth; 8/7.10 = 1.13). The compound bone displays a vertical and, in dorsal view, a rectilinear prearticular crest in V. l. ebusitana ( Fig. 6C), whereas in V. l. latastei this pre-articular crest is slightly medially inclined and curved medially in dorsal view ( Fig. 6F).

THE CAUDAL VERTEBRA FROM COVA DE CA NA REIA

The posterior caudal vertebra IMEDEA 106848 from Cova de ca na Reia is in a poorly preserved condition. Just a good portion of the neural crest, a part of the left prezygapophysis, a small portion of the postzygapophyses and the base of the neural spine is preserved, while the anterior margin of the zygosphene is eroded. The cotyle, the condyle and the pleurapophyses also are totally eroded.

The total ventral length of this fragmented vertebra is 1.92 mm. In anterior view, the dorsal surface of the zygosphene is convex ( Fig. 4P). The neural arch is moderately flattened in posterior view ( Fig. 4P, Q). The neural spine is considerably thick ( Fig. 4P, Q, S) and longer than high ( Fig. 4R). The hemapophyses are clearly individualized in the posterior half of the centrum and converging anteriorly ( Fig. 4T). Despite the hemapophyses are incomplete the left one is clearly incurved, i.e. the concavity is on the inner side.