New Paleogene Notohippids and Leontiniids (Toxodontia; Notoungulata; Mammalia) from the Early Oligocene Tinguiririca Fauna of the Andean Main Range, Central Chile
Author
Wyss, André R.
Author
Flynn, John J.
Author
Croft, Darin A.
text
American Museum Novitates
2018
2018-06-25
2018
3903
1
44
http://www.bioone.org/doi/10.1206/3903.1
journal article
10.1206/3903.1
0003-0082
Eomorphippus
Ameghino, 1901
TYPE
SPECIES
:
Eomorphippus obscurus
Ameghino, 1901
.
DIAGNOSIS (emended from
Simpson, 1967
): Marked hypsodonty of the upper and lower incisors, posterior premolars, and molars. Cementum lacking. Upper incisors moderately procumbent. I3 broad relative to I2 and I1. P4 more molariform than the anterior premolars, but lacking a distinct hypocone. Upper molars bearing hypocones, with a variable but deep cleft separating them from the protocone, the cleft blocked by the medial projection of what is likely the anterior end of the crochet. Other than the persistent major fossa, fossettes are obliterated early in wear.
Simpson (1967)
also listed P1–3 with notched or incomplete protolophs as diagnostic of
Eomorphippus
, but this feature applies to notohippids in general (Bond and López, 1993). He also considered lower molars with clefts anterior and posterior of the entoconid that variably develop into short-lived fossettids with wear as diagnostic of
Eomorphippus
, but this feature also appears to characterize a more inclusive group.