Natrix sp.

Codrea, Vlad A., Bordeianu, Marian & Venczel, Márton, 2021, Amphibians and squamate reptiles from the late Miocene of Fălciu (Eastern Romania), Palaeontologia Electronica (a 19) 25 (2), pp. 1-23 : 13

Natrix sp.

Figure 8 C-H

Material. UBB V 966/1-25 25 vertebrae, UBB V 967/1-5 five vertebrae.

Description. The centrum of the presacral vertebrae is relatively long, whereas the neural arch is moderately vaulted ( Figure 8 C-H). The neural spine in most specimens is broken off, and its remnants suggest that it was of relatively low height. The zygosphenal roof is more or less horizontal, whereas the anterior margin is shallowly convex. The apophyses are oval, whereas the prezygapophyseal processes, if preserved, are shorter than the length of the prezygapohyses; the posterior margin of the neural lamina is provided with a prominent epizygapophyseal spine. The subcentral surface is concave delimited laterally by the moderately developed subcentral ridges. The hypapophysis is sigmoid shaped, more prominent and directed posteroventrally in the anterior presacral vertebrae, whereas in the more posterior presacral vertebrae it is hooked backward with a rounded tip. The parapophyseal processes are long, flattened dorsoventrally with blunt anterior tip.

Remarks. The presacral trunk vertebrae display a combination of characters used to diagnose several members of the genus Natrix . Elongated vertebrae are typical for the fossil N. longivertebrata and for the recent N. natrix (Szyndlar, 1991b) . In N. longivertebrata the epizygapophyseal spines are usually lacking (Szyndlar, 2005), whereas in those from FP 1 are always prominent. In both, N. natrix and N. longivertebrata the prezygapophyseal processes are moderately long, blunt and flattened dorsoventrally, in contrast part of the vertebrae from FP 1 have short prezygapophyseal processes, whereas others are with long processes as seen in N. rudabanyaensis , known from the late Miocene (MN 9) of Rudabánya, N-Hungary (Szyndlar, 2005). Moreover, the parapophyses of Natrix sp. from FP 1 are obtuse, whereas some of the hypapophyses have their ventral margin flattened ( Figure 8F, G ), never observed in the above fossil or recent forms.

Figures

FIGURE 8. Fossil snake vertebrae from FP 1: A-B, Scolecophidia indet. (UBB V 965/1-2) in dorsal (A) and ventral (B) views; C-I, Natrix sp. (UBB V 967/1-5) in dorsal (C, D, I), ventral (F), anterior (E) and lateral (G,H) views; J, Colubridae indet. (UBB V 968/1) in ventral view. Scale bars (A-B; C-J) equal 2 mm.