A new species of Mesopropithecus (Primates, Palaeopropithecidae) from Northern Madagascar

Abstract

We diagnose new subfossil specimens belonging to the extinct palaeopropithecid, Mesopropithecus, from several caves at the Ankarana massif in northern Madagascar. They include three partial crania with mandibles, and the first vertebrae, ribs, clavicle, pelvis, ulna, and hand and foot bones of Mesopropithecus ever found. Several other postcranial elements are known for this northern variant of Mesopropithecus and for previously described species from central and southern Madagascar. The new materials cannot be accommodated in either currently recognized species of this genus and are, hereby, given the name Mesopropithecus dolichobrachion. M. dolichobrachion is the second new species of extinct subfossil lemur to be found in the caves of Ankarana. It is unlike the two previously described species of this genus primarily in its larger size, different limb proportions, and aspects of its long bone morphology. Most notable is the fact that this is the only species of Mesopropithecus with the forelimb longer than the hind limb- hence the name, the "long-armed" Mesopropithecus. Various characteristics place M. dolichobrachion phenetically closest (of species belonging to Mesopropithecus)to Babakotia radofilai, Archaeoindris, and Palaeopropithecus. If these similarities are derived specializations rather than primitive for palaeopropithecids, a new generic name will be required. © 1995 Plenum Publishing Corporation.