The Prosimian Fauna of the Fayum Eocene/Oligocene Deposits of Egypt

Abstract

After decades when only higher primates had been found in the Oligocene deposits of the Fayum, Egypt, a few isolated teeth of prosimians and a partial mandible of a tarsier were discovered there in the 1980s. These, assigned to the families Lorisidae, Omomyidae and a new genus and species, Afrotarsius chatrathi, are discussed and reviewed. Since 1990, a late Eocene locality in the Fayum, L-41, has been intensively explored, and in this older site a new suite of archaic higher primates has been recovered. Together with these anthropoideans, material of at least three new prosimians has been found. A skull and mandibles of the most complete of these, Plesiopithecus teras, was described in 1994. This appears to be the oldest strepsirhine yet discovered worldwide, and it has been assigned a position as a sister-group to the Lorisidea. In 1995, a cercamoniine adapid, Aframonius dieides, was also described from L-41. The description of a third new genus and species of prosimian from L-41 is presently in preparation. The previously described prosimians are here reviewed and their implications for understanding the overall prosimian radiation discussed.

Mammalian interchanges between Africa and Eurasia: an analysis of temporal constraints on plausible anthropoid dispersals during the Paleogene

“…Since then, numerous field expeditions to the Fayum led by Elwyn Simons have substantially improved our knowledge of the evolutionary history of African primates, notably that of early anthropoids. To date, the late Eocene-early Oligocene Fayum deposits have yielded more than 20 distinct primate forms, including anthropoids and prosimians (see Simons, 1995Simons, , 1998 for an overview). The high degree of anthropoid diversity in Egypt at the end of the Paleogene and the fact that some of the Fayum taxa may represent stem lineages of modern anthropoids have led several authors to regard Africa as the ancestral homeland of the anthropoid clade.…”

“…Chaimanee et al, 1997Chaimanee et al, , 2000aTakai et al, 2001Takai et al, , 2003Shigehara et al, 2002;, and discoveries of adapids with holarctic affinities in the Fayum (e.g. Simons et al, 1995;Simons, 1997Simons, , 1998 and Oman (Gheerbrant et al, 1993) challenge the 'orthodox' view of African anthropoid endemism.…”

Astragalar morphology of Afradapis, a large adapiform primate from the earliest late Eocene of Egypt

“…Over the last 15 years, increased exploration in the Eocene deposits of both the Jebel Qatrani and Birket Qarun Formations has also uncovered a diverse assemblage of ''prosimian'' primates. These fossils have had important implications for understanding both crown strepsirrhine origins and temporal changes in the taxonomic composition of early Afro-Arabian primate communities (Simons 1997(Simons , 1998Simons and Miller, 1997;Simons and Rasmussen 1994a;Simons et al, 1995;Seiffert 2003Seiffert , 2005bSeiffert , 2007a). …”

A clue to the Asian origin of euprimates

“…In the other northern continents euprimates already existed at the very beginning of the Eocene. Most researchers believe that D. martinezi shows a definitive affinity with adapiforms (Hartenberger and Marandat, 1992;Hartenberger et al, 1997;Simons, 1998;Fleagle, 1999;Gunnell and Miller, 2001), and it was regarded as an element involved in faunal exchange between Europe and northern Africa in the early Eocene (Hartenberger and Marandat, 1992). Thus, D. martinezi can hardly be regarded as a descendant of A. koulchii.…”