Abstract

The present paper describes a disarticulated skull of Allqokirus australis, Marshall & Muizon, 1988 a basal sparassodont (Methatheria, Mammalia) from the early Palaeocene of Tiupampa (Bolivia). The specimen includes the rostrum and palate with right premaxilla, both maxillae, left lacrimal, palatines and most upper teeth. The second largest element includes the frontals, the left squamosal, the parietals, the supraoccipital, the basisphenoid, the presphenoid, the alisphenoid, and part of the pterygoids. The nasals, basioccipital and exoccipitals are missing. Other elements are the left petrosal, the right jugal and squamosal, and both dentaries. The elements of the specimen allow for a good reconstruction of the skull, which is thoroughly described and compared to that of other sparassodonts and to the Tiupampa pucadelphyids, Pucadelphys and Andinodelphys. The dental morphology of Allqokirus australis is extremely similar to that of Patene simpsoni from the early Eocene of Itabora