Naja romani

description

DESCRIPTION The vertebra is large and robust with a centrum length of 9.2 mm and width of 9.7 mm. The CL / NAW (centrum length / width of interzygapophyseal constriction) ratio is 0.95. The constriction between the pre- and postzygapophyses is weakly developed. From the ventral view, the subcentral ridges are well developed and relatively straight. The subcentral grooves are deep. The hypapophysis is very long and laterally compressed. It is directed ventrally and slightly posteriorly, with its posterior tip being obtuse and protruding posteriorly to the level of the condyle. The neural spine is relatively long and low, and incomplete in its mid length. The neural arch is markedly vaulted. The synapophyses are broken, but the left parapophyseal process is partly preserved and projected anteriorly and slightly ventrally. The zygosphenal roof is concave in dorsal view, presenting a small prominence in the middle of its width that can be considered as minute median lobe. In anterior view, the zygosphenal roof is straight. The prezygapophyseal articular facets are nearly circular. The prezygapophyseal process is missing on the left side, but completely present on the right side where i

Naja romani (Hoffstetter, 1939) (Serpentes: Elapidae) from the late Miocene of the Northern Caucasus: the last East European large cobra

discussion

COMPARISON AND REMARKS The presence of hypapophysis is a typical distinctive feature for snakes of the families Natricidae, Viperidae, and Elapidae (Szyndlar 1991). Thus, the vertebra GIN 1145 / 305 can be assigned to one of these groups. The large size, robustness, and inclination of hypapophysis (directed ventrally rather than postero-ventrally) preclude the attribution of GIN 1145 / 305 to Natricidae. The shape and inclination of hypapophysis in GIN 1145 / 305 correspond to that of the vertebrae of Viperidae, however the vertebrae of the latter group have a dorso-ventrally depressed neural arch and larger cotyle and condyle. The laterally compressed hypapophysis and the very low neural spine observed in GIN 1145 / 305 are characteristic of Elapidae and “ Naja group ” (Szyndlar 1991). Elapid fossil finds often offer, well preserved cranial elements, which are useful keys for determining the fossil species. Accordingly, isolated elapid vertebrae are not very informative. Naja romani is currently the only recognized species of Naja in Central and Eastern Europe (a possible alternative opinion was announced by Quadros et al. 2019). The material herein can be assigned to N. romani ba

Naja romani (Hoffstetter, 1939) (Serpentes: Elapidae) from the late Miocene of the Northern Caucasus: the last East European large cobra

materials_examined

MATERIAL EXAMINED. — One precloacal vertebra GIN 1145 / 305, Solnechnodolsk locality, Northern Caucasus, Russia; late Turolian, MN 13.

Naja romani (Hoffstetter, 1939) (Serpentes: Elapidae) from the late Miocene of the Northern Caucasus: the last East European large cobra

description

Description. Fangs: Four isolated teeth are venomous fangs. They are tubular, with acute distal tips. The discharge orifice, located on the anterior surface of each fang, is elongate and gladiate-shaped. The discharge orifice extends, towards the proximal end, in the form of a visible suture. The latter condition is characteristic of elapid snakes, whereas in viperids the anterior surface of the fang is generally smooth. Relatively small dimensions of the fangs suggest that they either belonged to juvenile / subadult individuals or were replacement (non-functional) fangs. Vertebrae: Most vertebrae come from the middle trunk portion of the column. In the largest (but partly damaged) vertebra (HLMD-Ez 2151, Fig. 18 K-O), centrum length measures 7.1 mm, centrum width - 5.7 mm, and centrum length / centrum width ratio equals 1.25. At least in large vertebrae, the centrum is triangular in ventral view, with a flat or slightly concave ventral surface. The subcentral ridges are well developed, especially behind the paradiapophyses. The hypapophysis, preserved partly in few vertebrae, is thick, strongly inclined posteriorly and shows a straight anteroventral margin. The neural arch is rath

Amphibian and reptilian fauna from the early Miocene of Echzell, Germany