A lower jaw of Pondaungia cotteri from the Late Middle Eocene Pondaung Formation (Myanmar) confirms its anthropoid status

Pondaungia cotteri is the largest primate known from the Late Middle Eocene Pondaung Formation, Myanmar. Its taxonomic status has been the subject of much debate because of the fragmentary nature of its remains. Initially des cribed as an anthropoid, some authors recently have associated it with adap id primates. These debates have been fueled not only by the incompleteness of the fossils attributed to Pondaungia but also by the reticence of many a uthors to regard Asia as an important evolutionary theater for Eocene anthr opoids. During the November 1998 Myanmar-French Pondaung Expedition, a righ t lower jaw was discovered that yields the most nearly complete dentition o f Pondaungia cotteri ever found: it shows the complete horizontal ramus, al veoli for the second incisor and canine, three premolars, and three molars. The symphysis showed all characteristics of anthropoids but was unfused, T he canine root is large, the first premolar is absent, and the second premo lar is single-rooted, reduced, and oblique in the tooth row, as in anthropo ids. The premolars show a reduced mesio-distal length compared with the too th row, and their morphology is very similar to that of Amphipithecus mogau ngensis. Therefore, the two Pondaung taxa appear to be closely related to e ach other, with Siamopithecus as their sister taxon.