Scapherpeton, Cope, 1876

Cope, E. D., 1876, On some extinct reptiles and batrachia from the Judith River and Fox Hills beds of Montana, Proceedings of the Academy of Natural Sciences of Philadelphia 28, pp. 340-359 : 353-355

SCAPHERPETON, Cope.

Genus novum Batrachiarum. Vertebrae deeply biconcave, with opposed, but not continuous, foramina for the chorda dorsalis. Neural arch with zygapophyses, and well-developed neural spine. Centrum with vertically compressed, short diapophysis near the posterior extremity, a prominent hypapophysial keel, and prolonged neural spine. Supposed proximal limb bone with a branch-like trochanter. Supposed teeth in several rows, attached in shallow alveoli, those of the marginal series larger; the crowns obtusely conic and simple.

In the above diagnosis are expressed the general characters of a genus of probably tailed Batrachia which has left remains of several species in the Judith River beds of the Upper Missouri region. Although the vertebrae resemble no little those of clepsydrops, Cope, a rhynchocephalian lizard from supposed triassic or permian formations, the atlas is that of a batrachian. The limb bone probably belonging to it, is unlike that of any genus of the Proteida or Trachystomata , differing also from that of Menopoma , but approaching nearly that of the typical salamanders. The diapophyses are different in form from those of the Trachystomata Proteida and Amphiumidae , but resemble in their vertical compression those of Menopoma . They are generally broken in the specimens, but where preserved, are much shorter than in that genus, being even less produced than in most of the recent salamanders. The prominent keel of the median line below is not found in salamanders, and it has no posterior prolongation resembling the structure seen in Amphiuma and Caeciliidae . The produced neural spine is a character not found among tailed Batrachia , and the posterior direction which it takes reminds one of the Dinosauria more than anything else, and is not like the form seen in Lacertilia. It is a prolongation of the roof-like extension of the neural arch seen in some of the tertiary salamanders of France.

The structure of the proximal limb bone, and the form of the diapophyses of the vertebrae refer this genus with much probability to the Urodela . The produced neural arch, and the probably complex disposition of the teeth, indicate a family different from any of those now living. The biconcave centra place it nearest to the Amblystomidae .

The teeth above mentioned are attached to a fragment of a jaw-bone. The crowns are all imperfect, and mostly broken off. There are three series of smaller teeth and a marginal series of teeth of one hall‘ greater diameter. They exhibit a moderate pulp cavity, and the superficial investment of the crowns is not inflected. lt has a minute granular rugosity, and the bases of the teeth are rugose with impressed punctae. The teeth are described here because it is not known to which species they belong. It is, indeed, not certain, but only probable, that they belong to this genus.

Four atlases preserved indicate two species; one being more depressed than the other three, and the anterior cotyli therefore more transverse.

The vertebrae indicate four species. It is probable that they present some pecularities at different points in the same column, the caudals at least differing in some degree from the others. The characters of the species are quite well marked.