We describe a new extinct subspecies of the Javan lutung - Trachypithecus auratus sangiranensis - based on an isolated, tooth-bearing upper jaw. The specimen was in volcanic breccia situated between the Lower Pucangan and the Upper Kalibeng Formations 500 m south of the village of Sangiran, near Surakarta, central Java, Indonesia. The new fossil monkey bears morphological similarities to the two living species of leaf monkey from Java, Presbytis comata comata and Trachypithecus auratus auratus, and to the Middle Pleistocene form, Trachypithecus cristatus [=auratus] robustus, from Tegoean, central Java. It is significantly larger than any of these forms, and differs from them in details of dental anatomy. Because the greatest number of similarities are between the new fossil and Trachypithecus auratus subspecies, we designated the specimen as T. a. sangiranensis. The geochronological age of the breccia from which the fossil came, is 1.9 ± 0.05 Ma (million years), making T. a. sangiranensis one of the oldest fossil monkeys from eastern Asia.
All Science Journal Classification (ASJC) codes
- Ecology, Evolution, Behavior and Systematics
- Animal Science and Zoology