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Issue: Vol. 5873 No. 1: 20 Aug. 2026
Type: Article
Published: 2026-08-20
DOI: 10.11646/zootaxa.5873.1.8
Page range: 145-160
Abstract views: 966
PDF downloaded: 460

Reclassification of the smooth snake. Analysis of the rear fangs, venom system, and the cephalic anatomy of Coronella austriaca (Serpentes: Colubridae)

OPHIS; Museo Paleontologico e Centro Erpetologico; via bivio Putignano 3; 64100 Teramo; Italy
Via degli Orti 3; 6809 Medeglia; Switzerland
Reptilia smooth snake Coronella austriaca rear-fanged anatomy toxicofera

Abstract

The in-depth study of the cephalic anatomy of the smooth snake Coronella austriaca sheds new light on the biology of this species, representing an important step forward in understanding its ecology. A detailed study of the dentition of this species is presented here, describing for the first time the modified posterior maxillary fangs. Two specialized rear fangs are separated by the third to last tooth by a diastema, in turn spaced from the anterior maxillary teeth by a second diastema. The rear fangs are covered by sheaths connected to the venom/Duvernoy’s gland. Retracing the existing literature, we see how this gland in C. austriaca is predominantly serous, and its secretion can have significant effects on its preys and other animals. Analysis of specimens at different growth stages has shown that the growth of the maxillary bone and posterior fangs is isometric, while the parietal bone is subject to ontogenesis. Through several preparation steps, the presence of additional cephalic features previously unconsidered in this species has been documented, such as the presence of pits in the parietal shields and the corresponding foramina in the parietal bone that opens ventrally nearby the epiphysis. The presence of sheathed rear fangs has also been documented in the jaws of the sister taxon Coronella girondica. The nature and rationale for the opisthoglyphous/rear-fanged condition, shared by this species and other European colubrines, are discussed here.

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How to Cite

Paterna, A. & Meier, G. (2026) Reclassification of the smooth snake. Analysis of the rear fangs, venom system, and the cephalic anatomy of Coronella austriaca (Serpentes: Colubridae). Zootaxa, 5873 (1), 145–160. https://doi.org/10.11646/zootaxa.5873.1.8