A new primate from the Eocene Pondaung Formation of Myanmar and the monophyly of Burmese amphipithecids

<jats:p> The family Amphipithecidae is one of the two fossil primate taxa from Asia that appear to be early members of the anthropoid clade. <jats:italic>Ganlea megacanina</jats:italic> , gen. et sp. nov., is a new amphipithecid from the late middle Eocene Pondaung Formation of central Myanmar. The holotype of <jats:italic>Ganlea</jats:italic> is distinctive in having a relatively enormous lower canine showing heavy apical wear, indicating an important functional role of the lower canine in food preparation and ingestion. A phylogenetic analysis of amphipithecid relationships suggests that <jats:italic>Ganlea</jats:italic> is the sister taxon of <jats:italic>Myanmarpithecus</jats:italic> , a relatively small-bodied taxon that has often, but not always, been included in Amphipithecidae. <jats:italic>Pondaungia</jats:italic> is the sister taxon of the <jats:italic>Ganlea</jats:italic> + <jats:italic>Myanmarpithecus</jats:italic> clade. All three Pondaung amphipithecid genera are monophyletic with respect to <jats:italic>Siamopithecus</jats:italic> , which is the most basal amphipithecid currently known. The inclusion of <jats:italic>Myanmarpithecus</jats:italic> in Amphipithecidae diminishes the likelihood that amphipithecids are specially related to adapiform primates. Extremely heavy apical wear has been documented on the lower canines of all three genera of Burmese amphipithecids. This distinctive wear pattern suggests that Burmese amphipithecids were an endemic radiation of hard object feeders that may have been ecological analogues of living New World pitheciin monkeys. </jats:p>