Natrix cf. rudabanyaensis, Szyndlar, 2005

Venczel, Márton & Stiuc, Emanoil, 2008, Late middle Miocene amphibians and squamate reptiles from Taut ,, Romania, Geodiversitas 30 (4), pp. 731-763 : 759

publication ID	https://doi.org/ 10.5281/zenodo.4665621
persistent identifier	https://treatment.plazi.org/id/03D08790-FFD9-FFF4-5615-A66BFCB45555
treatment provided by	Felipe
scientific name	Natrix cf. rudabanyaensis
status

Treatment

Natrix cf. rudabanyaensis ( Fig. 16 View FIG A-F)

MATERIAL EXAMINED. — One quadrate ( ISER Tt-0502), 30 presacral vertebrae ( ISER Tt-0503/1-30).

DESCRIPTION

Quadrate

ISER Tt-0502 is slightly damaged at its anterodorsal margin; it might have belonged to a rather small individual ( Fig. 16A View FIG ). In lateral view, the bone widens distally while the quadrate crest is better defined above the trochlea quadrati. Dorsally the height of the crest is abruptly reduced merging into the anterior margin of the bone. In posterolateral view the bone is straight, somewhat thinner in the middle portion.

Vertebrae

The vertebral centrum is elongated and provided with a sigmoid hypapophysis. The distal portion of the hypapophysis strongly projects beyond the condyle and displays a rounded tip ( Fig. 16B View FIG , B’). The subcentral ridge is rather prominent posteriorly to parapophyses ( Fig. 16C, E View FIG ). The neural arch is moderately depressed, provided with large and posterolaterally projecting epizygapohyseal spines ( Fig. 16B, D View FIG ). In most specimens the neural spine is strongly damaged. However, small remnants of this structure indicate that the neural spine was longer than high. The anterior margin of the zygosphene is crenate with three distinct lobes. The prezygapophyseal articular facets are of oval shape, while the prezygapophyseal processes are moderately long, flattened dorsoventrally and obtuse distally.The paradiapophyses are well differentiated into diapophyseal and parapophyseal portions. The parapophyses are provided with a rather long parapophyseal process which has usually an obtuse anterior margin. In 12 measured presacral vertebrae the centrum length ranges between 2.84 and 4.86 mm, while the centrum width is between 1.72 and 3.3 mm. The centrum length/centrum width ratio range

is 1.34-1.65 (mean = 1.5). The vertebraefrom

Late middle Miocene amphibians and reptiles from Taut,, Romania

the posterior presacral region are more depressed dorsoventrally and provided with a low and long neural spine ( Fig. 16F View FIG ).

REMARKS

The fossils from Tauţ closely resemble Natrix rudabanyaensis Szyndlar, 2005 by their relatively small size, moderately developed subcentral ridges, round- ed distal hypapophyseal tip and similar centrum length/centrum width ratio ( Szyndlar 2005). In N. natrix (Linnaeus, 1758) and N. merkurensis Ivanov, 2002 , in both of which the hypapophysis has a rounded tip, the centrum length/centrum width ratio is distinctly higher. In several other members of the genus the hypapophysis is provided with a pointed distal tip (e.g., N. longivertebrata Szyndlar, 1984 , N. maura (Linnaeus, 1758) , N. sansaniensis (Lartet, 1851) , N. tessellata (Laurenti, 1768)) , and with variable centrum length/centrum width ratio ( Szyndlar 2005). In Neonatrix natricoides Augé & Rage, 2000 , known from the middle Miocene (MN 6) of Sansan (sometimes regarded as a member of the genus Natrix  Szyndlar 2005 ), the prezygapophyseal processes and the hypapophysis are extremely short, while the neural lamina usually lacks an epizygapophyseal spine ( Augé & Rage 2000).