Philip the Arab Antoninianus ca. 248AD 3.99g

IMP PHILIPPVS AVG. Radiate head right.
SAECULARES AVGG. exergue VI. Goat or hind walking left. 

RIC IV-III, 23.

The footnote mentions that the animal's horns are "not sunk over the back, perhaps the same as a British Museum coin with reverse of a stag with long, straight horns, upright, walking left."

Contributed by Mike Smith.