Leptocyon, MATTHEW, 1918

Maguire, Kaitlin Clare & Schmitz, Joshua X. Samuels and Mark D., 2022, The fauna and chronostratigraphy of the middle Miocene Mascall type area, John Day Basin, Oregon, USA, PaleoBios 35, pp. 1-51 : 13

LEPTOCYON MATTHEW, 1918

Leptocyon sp. FIG. 6A , �

Referred specimens —Right dentary fragment with p3 and p4, JODA 2312; right dentary fragment with p4, JODA 2313.

Occurrence —JDNM-4*.

Description —Referral to Leptocyon is based on both specimens displaying diastemata separating the premolars (characteristic of L eptocyon and Vulpes Frisch, 1775 ) and the presence of weak premolar cusplets ( Tedford et al. 2009). As described by Tedford et al. (2009), the lower premolars are lower-crowned (note the p3 of JODA 2312) than the late Barstovian and Clarendonian L. vafer Leidy, 1858 . Dimensions of the premolars fall within the range of L. leidyi ; however, definitive diagnostic elements are not preserved. Measurements for each are JODA 2312: p3 ap= 5.38 mm, p4 ap= 6.82 mm, t= 3.03 mm; JODA 2313: p4 ap= 7.48 mm, t= 3.01mm.

Remarks —These specimens were collected by the Weatherfords without records of provenance, making it difficult to place them into a stratigraphic framework. Occurrence of Leptocyon in the Mascall Formation is not surprising given its wide distribution in the early Barstovian, including records from California, Colorado, Montana, Nebraska, and New Mexico, as well as its presence at several Arikareean sites from the John Day Formation of Oregon ( Tedford et al. 2009).

Figures

Figure 6. Leptocyon sp. A. Right dentary fragment with p3- p4 in lateral view, JODA 2312. B. Dentary fragment with p4 in lateral view, JODA 2313. Scale bar=1cm