Mandagomphodon hirschsoni: a Traversodont Cynodont From Anisian Triassic Tanzania

The Traversodontid Cynodont Mandagomphodon hirschsoni from the Middle Triassic of the Ruhuhu Valley, Tanzania

Author:

James Hopson

Abstract:

Mandagomphodon hirschsoni (gen. nov., comb. nov.) is one of three species of traversodontid cynodont placed in Scalenodon [type species S. angustifrons (Parrington, 1946)] by Crompton (1972). It is based on a partial skull and lower jaws from the Middle Triassic of the Ruhuhu Valley, southwestern Tanzania. The upper postcanine teeth were used to diagnose species of Scalenodon, but newer traversodontid material indicates that the three species represent distinct genera. Material of “S.” hirschsoni, except for the postcanines, has not been described. It is unusual among traversodontids in having only three upper incisors, which are enlarged and procumbent. Three enlarged, procumbent anterior lower teeth are interpreted as two incisors and a canine. Analysis of postcanine wear facets indicates that the power stroke of the lower teeth was entirely in a posterior direction, including a slightly downward and backward grinding movement at the end of the stroke.