Caracterización de los tarsales proximales de Campanorco inauguralis (Notoungulata, Typotheria)

ARMELLA, MATÍAS ALBERTO; GARCÍA LÓPEZ, DANIEL ALFREDO

San Miguel de Tucumán

Congreso; XX Congreso Geológico Argentino; 2017

Northwestern argentina was an important area of early diversification for several groups of native ungulates during the âleogene, particularly notoungulates. It is well known that postcranial elements can provide characters for phylogenetic analyses and important clues for paleobiological inferences. Recently, new cranial and postcranial remains, assigned to Campanorco inauguralis (Notoungulata, Typotheria), were recovered at the levels of the Upper Lumbrera Formation. Several authors indicated that cranial and dental features of this taxon show affinities with Mesotheriidae. This study presents a characterization of the proximal tarsals of Campanorco inauguralis from Salta Province, Argentina. On the basis of a comparative analysis, the convex and vertically oriented ectal facet, the slightly asymmetrical and trapezoidal-shaped tibial trochlea, and the distal prolongation of the medial crest on the astragalar neck are useful diagnostic features for this taxon. In turn, there are not undoubted postcranial features to link Camponorco inauguralis with Mesotheriidae as postulated in previous hypothesis. In this sense, the tarsals show a generalized morphology among basal notoungulates, supporting its basal position among Typotheria.