Observations on the sk ulls of fossil and extant echidnas (Monotremata: Tachyglossidae).

Abstract

The anatomies of four well-preserved, fossilised tachyglossid skulls from Naracoorte, South Australia are described and compared with that of a fossilised skull from north-western Tasmania, with those of 13 extant Long-beaked Echidnas, Zaglossus bruijnii, from New Guinea, and with those of II Short-beaked Echidnas, Tachyglossus aculeatus. The difference in structure and proportions of the rostrums, palates and craniums of the fossil forms from those of Z. bruijnii and T. aculeatus are so great that it is concluded that the former should be placed in a new genus; the name Megalibgwilia is proposed. From the conformation of the rostrum and palate it is suggested that the principal prey of Megalibgwilia was large insects such as scarab and moth larvae, not oligochaete worms as is the case with Z. bruijnii.