First report of Eozygodon (Mammutidae, Proboscidea) in Eurasia

Abstract

ABSTRACT Mammutidae are one of the two main branches of the Elephantiformes. Fossil records of Mammutidae were reported from the late Oligocene to the late Pleistocene throughout Africa, Europe, Asia, and North America. However, Eozygodon, one of the primitive members of Mammutidae, was found only in Africa with very few representatives. In this paper, a juvenile mandible and several isolated cheek teeth from the middle Miocene Lengshuigou Formation, Lintong, China, which were previously identified as Gomphotheriidae gen. et sp. indet., are re-evaluated. The cheek teeth display clear zygodont features, thus should be attributed into Mammutidae. Furthermore, the lower tusks are elongated with a longitudinal dorsal groove, resulting in a pyriform cross-section. These features are unique in Eozygodon within Mammutidae, and therefore the Lintong specimens are identified as Eozygodon sp. herein. This is the first report of Eozygodon in Eurasia, and the material might represent the most ancestral mammutids from China so far. The Lintong Eozygodon sp. reveals an interchange event of Eozygodon from Africa to Asia possibly at early Miocene through the ‘Gomphotherium landbridge’, or via a further ‘southern route’ passing through the Indian Subcontinent.