Charina, Gray, 1849

Jacisin Iii, John J. & Lawing, A. Michelle, 2024, Fossil snakes of the Penny Creek Local Fauna from Webster County, Nebraska, USA, and the first record of snakes from the Early Clarendonian (12.5 - 12 Ma) of North America, Palaeontologia Electronica (a 2) 27 (1), pp. 1-42 : 8

Genus CHARINA Gray, 1849

Diagnosis. As diagnosed in Head (2015), Charina possesses a lobate neural spine that is laterally expanded similar to other Charinainae, and the pterapophyses are anteriorly directed in caudal vertebrae ( Kluge, 1993; Szyndlar, 1994). Charina also exhibits a non-U-shaped zygosphene in dorsal view, a strongly concave zygosphene in anterior view, a relatively depressed neural arch, an incised posterior edge of the neural arch, and no paracotylar foramina ( Holman, 2000).

Remarks. The fossils described here are similar in size and morphology to known species of Charina . The longer neural spine, the V-shaped (dorsal), strongly concave (anterior) zygosphene, and the depressed neural arch with a relatively deeply incised posterior edge suggest that these vertebrae do not belong to the genus Lichanura ; however, it should be noted that Bell and Mead (1996) have observed some intraspecific variation in these characters. As in Parmley and Walker (2003), we instead attribute this fossil to the genus Charina based on the relative length of the neural spine, which is greater than that of Lichanura , and the lack of juvenile characteristics despite being relatively small in size. Parmley and Walker (2003) have observed that Lichanura of a similar size show juvenile characteristics such as a short, high overall morphology, thin neural arch, thin and highly arched zygosphene, exceptionally short neural spine, enlarged neural canal, and a condyle that appears too large for the centrum, none of which are visible in this specimen.