A new baluchimyine rodent from the Late Eocene of the Krabi Basin (Thailand): palaeobiogeographic and biochronologic implications

Abstract

The latest fieldworks in the Krabi Basin from Thailand have provided accurate stratigraphic, magnetostratigraphic and faunal settings. A complete left maxilla of a new baluchimyine rodent, Baluchimys krabiense nov. sp., described herein, has been found in the Bang Mark pit from the Krabi mine for which a Late Eocene age is attributed. The discovery of such an Eocene baluchimyine in South Asia casts serious doubts on the previous Early Miocene age assignment for Pakistani baluchimyines. Moreover, the comparison with a Late Eocene taxa from North Africa allows us to suggest close phylogenetic relationships, implying that this group had a widespread African–Asian distribution during the Palaeogene. In that context, the endemism assumption related to the Indian Subcontinent isolation throughout the Eocene until the Early Miocene is refuted here.