New Zealand’s St Bathans Fauna: an update on its composition and relationships

Discovery of an Early Miocene terrestrial fauna near St Bathans, Otago was made during stratigraphic mapping in the 1970s. Investigation of this site, the only insight into the terrestrial vertebrate faunas of New Zealand for the whole Tertiary, began anew in 2001 with the first fieldwork to recover fossils. Prior to our work, the fauna was known to include two presumed waterfowl species and a crocodilian. First to be published as a result of these renewed investigations, in 2006, was New Zealand’s inaugural terrestrial mammal, a member of a possibly unknown basal group and dubbed the waddling mouse. The first holistic analysis of the fauna was published in 2007. In this, the fauna was named the St Bathans Fauna, and 23 taxa of birds were reported, with six species formally described, as well as the presence noted of sphenodontids, skinks, geckoes, bats, abundant fish and a crocodilian. The discovery of the ‘waddling mouse’ was the stimulus for establishment of a joint UNSW, University of Adelaide, Museum of New Zealand Te Papa Tongarewa and Canterbury Museum project to continue investigation of the fauna in the period 2007-2009. Here we summarize the fauna known to date.