Reconstructing the origin and early evolutionary history of anthropoid primates (monkeys, apes, and humans) is a current focus of paleoprimatology. Although earlier hypotheses frequently supported an African origin for anthropoids, recent discoveries of older and phylogenetically more basal fossils in China and Myanmar indicate that the group originated in Asia. Given the Oligocene-Recent history of African anthropoids, the colonization of Africa by early anthropoids hailing from Asia was a decisive event in primate evolution. However, the fossil record has so far failed to constrain the nature and timing of this pivotal event. Here we describe a fossil primate from the late middle Eocene Pondaung Formation of Myanmar,
Afrasia djijidae
gen. et sp. nov., that is remarkably similar to, yet dentally more primitive than, the roughly contemporaneous North African anthropoid
Afrotarsius
. Phylogenetic analysis suggests that
Afrasia
and
Afrotarsius
are sister taxa within a basal anthropoid clade designated as the infraorder Eosimiiformes. Current knowledge of eosimiiform relationships and their distribution through space and time suggests that members of this clade dispersed from Asia to Africa sometime during the middle Eocene, shortly before their first appearance in the African fossil record. Crown anthropoids and their nearest fossil relatives do not appear to be specially related to
Afrotarsius
, suggesting one or more additional episodes of dispersal from Asia to Africa. Hystricognathous rodents, anthracotheres, and possibly other Asian mammal groups seem to have colonized Africa at roughly the same time or shortly after anthropoids gained their first toehold there.
A skull and mandible of the new species Dicerorhinus gwebinensis sp. nov. of Rhinocerotidae (Mammalia, Perissodactyla) is described. The material is collected from the upper part of the Irrawaddy sediments (PlioPleistocene) in central Myanmar. D. gwebinensis sp. nov. is morphologically more similar to the extant species D. sumatrensis (Sumatran rhinoceros) than to other species of the genus but differs from D. sumatrensis in having the comparatively shorter nasal, the more concave dorsal profile of the skull, the more elevated occiput and presence of molar crista in M3 ⁄ . This is the first discovery of Dicerorhinus in the upper Miocene to lower Pleistocene of the Indian subcontinent and Mainland Southeast Asia, and fills the chronological and geographical gap of this lineage in Asia. The Dicerorhinus clade probably migrated into Southeast Asia from East Asia by the Pliocene or early Pleistocene. This hypothesis is supported by the scarcity or absence of this clade in the Neogene mammalian fauna of the Indian Subcontinent.
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