Discovery of an embrithopod mammal (Arsinoitherium?) in the late Eocene of Tunisia

• We describe a new Paleogene fossil locality in Tunisia.
• New probable remains of the emblematic large mammal Arsinoitherium are described.
• The enamel microstructure reveals affinities with derived Embrithopoda.

Dental and postcranial remains (an atlas, carpus and metacarpus elements, and a part of the pelvic girdle) of an embrithopod mammal are described from Bir Om Ali, Tunisia, a new late Eocene locality. The enamel microstructure of a tooth fragment found in association shows ‘arsinoitheriid radial enamel’, an enamel condition which is characteristic of Arsinoitherium (Arsinoitheriidae, Embrithopoda). Although the postcranial elements slightly differ in size and morphology from those of Arsinoitherium zitteli (late Eocene to early Oligocene), we tentatively refer this new Eocene Tunisian material to that genus. These fossils represent the first known embrithopod from the Eocene of Tunisia.