MORPHOLOGICAL AND GENETIC-VARIATION IN THE BEARDED TOMB BATS (TAPHOZOUS, EMBALLONURIDAE) OF NUSA-TENGGARA, INDONESIA

A total of 111 adult specimens of Bearded Tomb Bats (Taphozous spp.) w as examined morphologically and 58 were examined by protein electropho resis from recent collections made from islands in Nusa Tenggara (Lomb ok, Sumbawa, Moyo, Alor, Timor, Semau, Roti and Savu). Multiple regres sion analysis revealed no significant sexual dimorphism; of the 30 cha racters considered, four skull characters were influenced by the age o f adults as determined by their molar tooth wear. Principal component analysis produced two distinct clusters of specimens. These clusters r elate to the species Taphozous melanopogon Temminck, 1841 and T. achat es Thomas, 1915. Canonical variate (discriminant) analysis of skull ch aracters alone allowed allocation of 100 percent of cases to their cor rect species. The Rotinese population of T. achates differs somewhat m orphologically from those of Savu and Semau. Protein electrophoresis r evealed that nine of the 31 loci scored were variable within or betwee n populations. The measured average heterozygosity within populations ranged from 0.039 on Lombok I. to zero on Semau and Savu I. Two of the nine variable loci showed highly significant interpopulation variatio n (Gox and Pep-B). The genetic data separate the same two broad groups as indicated by the morphological analysis (T. melanopogon and T. ach ates). Although the average genetic distance between these two species is small (Nei distance 0.031) there is a low level of intrapopulation variation. Taphozous melanopogon and T. achates are rediagnosed. The morphological and genetic variation of these taxa are discussed in the context of the historical biogeography of their island populations.