Electrophoretic studies of the systematic and biogeographic relationships of the Fijian bat genera Pteropus, Pteralopex, Chaerephon and Notopteris.

Abstract

Allozyme variation at 24 - 29 presumptive loci was used to examine the systematic relationships between Fijian bats and those from neighbouring areas such as Vanuatu, Solomon Islands, New Caledonia, New Guinea and Australia. Genetic data indicate that the Fijian bat fauna contains highly divergent taxa as well as some populations that are virtually indistinguishable electrophoretically from conspecifics in neighbouring islands groups, particularly species shared with Vanuatu. The endemic Fijian monkey-faced bat Pteralopex acrodonta, had a level of distinctiveness from two of its congeners in the Solomon Islands comparable to that between different genera. There was also considerable electrophoretic variation within what is generally considered a single species, the northern freetail-bat Chaerephon jobensis. The Australian form, C. j. colonicus, shows levels of divergence from the Fiji/Vanuatu subspecies, C. j. bregullae, consistent with that of a distinct species. C. j. solomonis from the Solomon Islands appears to represent a third species within this group. Moderate levels of divergence were found within the one subspecies of long-tailed flying-fox Notopteris macdonaldii sampled from Fiji and Vanuatu. In contrast to Pteralopex and Chaerephon, close affinities were found between and within several other southwest Pacific bat species, in particular, the two different subspecies of insular flying-fox Pteropus tonganus from Fiji, Vanuatu and the Solomon Islands. Low levels of genetic divergence were also found between P. tonganus and the morphologially similar spectacled flying-fox P. conspicillatus from Australia and New Guinea. The Samoan flying-fox Pteropus samoensis appeared to be most closely allied to the Temotu flying-fox Pteropus nitendiensis, from the Solomon Islands.