Anguidae indet., 2022
|
publication ID |
https://dx.doi.org/10.3897/fr.25.83781 |
|
publication LSID |
lsid:zoobank.org:pub:7A16698D-4F18-48D2-9D96-51A6E0CC15AC |
|
persistent identifier |
https://treatment.plazi.org/id/FF69E9F7-FD8C-51E4-A2EE-B13293164477 |
|
treatment provided by |
by Pensoft |
|
scientific name |
Anguidae indet. |
| status |
|
Anguidae indet. View in CoL View at ENA
Fig. 16 View Figure 16
Material.
Four caudal vertebrae HLMD-Ez 1981-1984, 73 osteoderms HLMD-Ez 1985-1987 (figured ones), HLMD-Ez 1988 (the remaining osteoderms).
Description.
Caudal vertebra: The caudal vertebrae (Fig. 16A-E View Figure 16 ) are elongate and narrow. Both pre- and postzygapophyses are small; thus, there is a typical tendency toward the elongation of the centra in caudal vertebrae and a relative reduction of all processes. The cotyle and condyle are dorsoventrally depressed. The neural canal is a tunnel-like structure here. The haemapophyses are fused to the posterior portion of the centrum, but, unfortunately, their ends are broken off. Only the bases of the anteroventrally oriented transverse processes (pleurapophyses) are preserved, being dorsoventrally slightly flattened. They are pierced by a foramen. The distal portions are, however, broken off. The neural spine is posterodorsally oriented, rather slim and pointed. The transverse autotomic split is present.
Remarks.
The presence of an autotomic split indicates that we can exclude Pseudopus , in which only autotomic foramina are developed (see Čerňanský et al. 2019). In contrast, the autotomic split is present in both Anguis and Ophisaurus (see Hoffstetter and Gasc 1969).
Osteoderm: A large number of osteoderms of several types are preserved in the material. The first type represents wide, rectangular osteoderms (e.g., HLMD-Ez 1985, Fig. 16G-F View Figure 16 ). There is a low medial ridge running along their central regions. However, the ridge is almost indistinctive and restricted only to the sculptured region. The anterior overlap surface is large and occupies about one-third of the external surface. The lateral bevel is the highest close to the overlap surface. The posterior portion of the external surface is ornamented. The ornamentation is formed by several tubercles, pits, long grooves, and ridges diverging from the central region. Three foramina pierce the central part of the internal surface. The second type (and the most common, as represented by HLMD-Ez 1986, Fig. 16H View Figure 16 ) includes slender osteoderms. In those, the medial ridge runs along the entire external surface, including both ornamented and anterior overlap surface. The third type (rare, HLMD-Ez 1987, Fig. 16I View Figure 16 ) is represented by a flat and wide osteoderm without a medial ridge.
The differences might very likely represent individual variability and a different body topology from where osteoderms originated (e.g., ventral vs. dorsal armour; see, e.g., Čerňanský and Klembara 2017). Their determination to the alpha taxonomy level is currently impossible. Nevertheless, they resemble osteoderms of Ophisaurus , but other taxa cannot be excluded.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.