Ommatotriton Gray, 1850
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publication ID |
https://doi.org/10.1186/s13358-024-00332-7 |
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persistent identifier |
https://treatment.plazi.org/id/E86287BF-FFEE-FFFF-BA71-A7CEFCACFD04 |
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treatment provided by |
Felipe |
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scientific name |
Ommatotriton Gray, 1850 |
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Ommatotriton Gray, 1850 View in CoL
cf. Ommatotriton sp.
Figure 2 View Fig
Material. Spilia 4: three trunk vertebrae ( UU SP4 515, UU SP4 516, and UU SP4 720).
Description.
Tese three vertebrae from Spilia 4 are rather small
( Fig. 2 View Fig ). Te largest one, UU SP4 720 ( Fig. 2k–n View Fig ), is 2.8 mm long, whereas the other two are either about 1.5 mm ( UU SP4 515; Fig. 2a–e View Fig ) or 1 mm ( UU SP4 516; Fig. 2f–j View Fig ) in length. Tey are opisthocoelous, with a moderately or well-developed neck separating the anterior condyle from the main body of the vertebral centrum. Te anterior surface of the condyle is flat and vertical. Te ventral portion of the centrum is broken away in UU SP4 515 ( Fig. 2e View Fig ), but two large subcentral foramina are visible on the ventral surface at least in UU SP4 720 ( Fig. 2n View Fig ). Te transverse processes are slender and posterolaterally directed. A very wide foramen is visible anterior to the parapophyses. Te ventral and zygapophyseal crests are moderately to well developed. Te ventral lamina composed by the ventral crests goes from subtriangular (in UU SP4 515) to rhomboidal (in UU SP4 720). Te neural arch is high and dorsally depressed. Posteriorly, it rises distinctly. Te arch defines a wide neural canal, which is wider than the anterior condyle in anterior view. Te prezygapophyses are badly preserved in UU SP4 720, but are complete in the other two specimens: they are small and elongated, subelliptical in shape and slightly inclined in dorsolateral direction. Te straight anterior margin of the neural arch is located roughly at the end of their anterior third. Te postzygapophyses, on the other hand, are preserved only in UU SP4 516, sharing a similar shape with the prezygapophyses and ending in line with the posterior margin of the neural arch. Te neurapophysis is high. Its anterior end is located roughly in line with the posterior end of the prezygapophyses, not far from (but not in contact with) the anterior margin of the neural arch. Te anterior margin of the neurapophysis is inclined in UU SP4 515 and straight in UU SP4 516 (not preserved in UU SP4 720). Te dorsal margin is sufficiently preserved only in UU SP4 516, which shows a nearly straight dorsal outline in lateral view. A posterior, triangular expanded area touching the posterior margin of the neural arch is visible in the same specimen, but its presence in the other vertebrae cannot be evaluated due to poor preservation. Te posterior end of the arch is completely missing in UU SP4 720, badly preserved in UU SP4 515 and more preserved in UU SP4 516. At least the latter clearly displays a wide, deep and U-shaped notch on the posterior margin. In spite of the poor preservation, the posterior margin of the arch appears slightly wavy in UU SP4 515, but it is not clear whether a real notch was present or not .
Remarks. Te referral of these vertebrae to small salamandrids is supported by the opisthocoelous centrum and the posterior notch on the neural arch ( Ratnikov & Litvinchuk, 2007). Te combined presence of high neural crest, high neural arch, well-developed anterior zygapophyseal crests, and especially the very wide foramen at the base of each parapophysis is diagnostic for Ommatotriton (Macaluso et al., 2023b) . Te remaining morphology is also comparable with the one described for trunk vertebrae of Ommatotriton ophryticus (Berthold, 1846) by Ratnikov and Litvinchuk (2007), except mainly for the distinctly smaller size of the Greek fossils. Te very wide neural canal of UU SP4 516 could be a juvenile condition, thus accounting for the very small size of at least this vertebra. In any case, we treat our identification as only tentative here due to the significant difference in size of these fossils compared to extant representatives of the genus.
| UU |
University of Uppsala |
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