Amphipithecus and Pondaungia are enigmatic fossil primates discovered from the Pondaung district, Central Myanmar (Burma). Since the first discoveries early in this century, many researchers have discussed about their phylogenetic position: some authors regarded them as anthropoid primates (e. g. Pilgrim, 1927; Colbert, 1937), some as a kind of condylarths (Koenigswald, 1965), and others as lemuroid primates (Szalay, 1970; Szalay and Delson, 1979). Even after the second specimens discovered in 1970's, same controversy has been repeated by many researchers (Ba Maw et al., 1979; Ciochon et al., 1985; Ciochon and Holroyd, 1994).
In 1997 several new specimens of Amphipithecus and Pondaungia were discovered in the Pondaung district by Myanmar researchers (Anonymous, 1997). These new fossils provide us a plenty of information about their mandibular morphology, and suggest a possible plylogenetic relationship among Pondaung primates and Siamopithecus, which was discovered from Krabi, Thailand (Chaimanee et al., 1997).
The geological age of the Pondaung primates and Krabi primate have also been discussed by several workers (e. g. Holroyd and Ciochon, 1994; Ducrocq et al., 1992; 1995). In this paper we compared the fossil mammal lists of the Pondaung, Krabi, and several Southern Chinese Eocene faunas. Our conclusion is as follows: the Pondaung fauna is most similar to the Naduo fauna in Yunnan Province, China, and probably slightly older than the Krabi fauna in Thailand. The geological age of the Pondaung fauna is likely to be the Late Eocene rather than the late Middle Eocene advocated by Holroyd and Ciochon (1994).
More detailed comparisons among Middle to Late Eocene mammal faunas in Myanmar, Thailand, China, and Mongolia will make clear the evolutionary history of the Eocene primates in East Asia.

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Since the 1950's numerous hominoid fossils have been discovered in the Yunnan Province, southern China, from several late Miocene-early Pliocene localities. These fossil specimens occur together with small prosimian fossils, and can be divided into two groups by the overall size.
The larger specimens have formerly been classified into two taxa: a larger species, “Sivapithecus yunnanensis”, and a smaller one, “Ramapithecus lufengensis”. At present, however, they are generally regarded as a single taxon, Lufengpithecus lufengensis, which shows a remarkable sexual dimorphism. In spite of the abundant fossil materials, the phylogenetic position of Lufengpithecus is still obscure. Some researchers regard it to be a close relative of Sivapithecus from the middle Miocene Siwalik sediments in India and Pakistan, while others suggest more affinities to European dryopithecids denying a close relationship between Lufengpithecus and Sivapithecus. Therefore, the hypothetical relationship between Sivapithecus, Lufengpithecus, and extant Pongo need to be reconsidered.
On the other hand, smaller specimens are identified as a single species, Laccopithecus robustus, which has been regarded as an ancestral group of living gibbons. Recently many researchers, however, advocate that Laccopithecus is closely related to European pliopithecids but not to extant hylobatids.
Thus, the phylogenetic positions of Yunnan hominoid fossils are now in debate. The evolutionary process of eastern Asian hominoids should be reconstructed considering a possible phyletic relationship with European hominoid species.

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