Informace o publikaci
Description of the cranial anatomy of an exceptionally well-preserved skull of Sauropleura scalaris (Nectridea: Urocordylidae) from the Upper Carboniferous of the Czech Republic using micro-computed tomography
| Autoři | |
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| Rok publikování | 2022 |
| Druh | Konferenční abstrakty |
| Fakulta / Pracoviště MU | |
| Citace | |
| Popis | Here we report on a small, 14.5 mm long, articulated skull and mandible of Sauropleura scalaris with well-preserved dermal bones, and associated axial skeleton including almost complete tail region. The skull was for the first time scanned by the high-resolution micro-CT tomography (GE phoenix v|tome|x L240) and processed in the medical software ITK-SNAP v. 3.8.0. Consequently, the direct comparison of the morphology of ventral and dorsal surfaces of several dermal skull bones, as well as nature of their connections, is possible. In contrast to the previous skull reconstruction, the specimen reported here suggests the jugal interrupts the connection between maxilla and quadratojugal. The later bone is also excluded from the posterior margin of skull by squamosal. Posteroventral part of the skull shows the first evidence of partially ossified braincase in Sauropleura scalaris. It consists of the opisthotic with conspicuous paroccipital process well corresponding to the morphology reported in other nectrideans, as well as possible exoccipital. With the skull length of only 14.5 mm, this indicates the neurocranium at least partially ossified at the relatively early stage of ontogeny. Labial surface of dentary bears a series of a few pits and elongated grooves, which represent the lateral line system of mandible. This is the first evidence of such a structure in Urocordylidae and adds to another support for a fully aquatic ecology inferred for the group. Additionally, almost complete tail region preserves the highest number of caudal vertebrae reported in Sauropleura, with estimated total count equal to or even higher than in long-tailed urocordylines. |