Oligopithecus

Abstract: In 1987 and 1988 fossils of two previously unknown genera and species of Egyptian early Tertiary Anthropoidea were discovered in the Fayum Depression of Egypt These are much older than all other Fayum, Oligocene primates and are believed to be Eocene in age These genera, here named Catopithecus and Proteopithecus, come from a new Fayum site, L-41, and resemble Oligopithecus from the Jebel Qatrani Formation (lower sequence) at quarry E They are here placed with the latter in a subfamily, Oligopithecinae, that is ranked in the Propliopithecidae The level of L-41 is separated from quarry E by at least one major unconformity and 47 m of section Only a maxilla of Proteopithecus is known Its molars and premolars resemble those of later Fayum Propliopithecus and Aegyptopithecus and do not resemble those of Apidium and Parapithecus, all of which come from the Jebel Qatrani Formation, upper sequence The type specimen of Catopithecus confirms a lower dental formula of 2-1-2-3, as in Catarrhini These species appear to be the oldest primates undoubtedly related to humans Their dental anatomy points to a derivation of Anthropoidea from Eocene adapids

Abstract: A RECENT article by Szalay1 could be taken to be a definitive statement of the relationships of two of the earliest known specimens that can possibly be related to the origin of the catarrhine primates, the group which includes Old World monkeys, apes and men. Each of the fossils concerned—Amphipithecus from the late Eocene of Burma and Oligopithecus from the Oligocene exposures in the Fayum, Egypt—is known only from a single specimen. A different assessment of their relationships is presented here. Colbert has already shown2,3 clearly and competently why the teeth and tooth cusps of Amphipithecus resemble those of catarrhines. I here outline some observations on how jaws function and why and how the jaw of Amphipithecus can be demonstrated to be similar to or different from those of other animals.

Abstract: Hoanghonius found in the "River section" of Yuanqu Basin, Shanxi Province is the earliest discovered Eocene Primates of China. The materials are a fragmentary lower jaw with only two lower molars on it and an isolated upper molar. For above specimens Zdansky (1930) named as Hoanghonius stehlini and pointed out that the lower cheek teeth of this animal resembled those of notharctids while the upper molar was similar to omomyids, so the systematic position of Hoanghonius was Primates incertae sedis. Later on Hoanghonius was placed in Omomyidae (Hill, 1955; Woo and Chow, 1957; Romer, 1966). But in the past twenty years it was normally placed to Adapidae (Szalay, 1974; Gingerich. 1976; 1977; Rasmussen and Simons, 1988). Someone, however, thought it to be related to living cheirogleids of Madagasga (Schwartz, 1986). Owing to some similarities in lower cheek teeth between Hoanghonius and earlier anthropoids-- Oligopithecus, some people believed that Hoanghonius might have something to do with origin of anthropoids. Why the systematic position of Hoanghonius is so different? The main reason is no complete materials have been found. In the past five years we worked in Yuanqu Basin and found precious Eosiamis as well,as many other mammalian fossils, including incomplete lower jaws and isolated teeth of Hoanghonius. Fortunately we discovered a rather complete lower jaw of Hoanghonius in the recent field work, which is the best specimen ever found since it has been created. This specimen not only provides many new morphological information but also is useful for determining Hoanghonius' systematic position and its relationships with early anthropoids.