Phylogenetic position of Apis nuluensis of northern Borneo and phylogeography of A-cerana as inferred from mitochondrial DNA sequences

The montane honeybee, Apis nuluensis, is adapted to the Mt. Kinabalu highla nds of Borneo. We analyzed the phylogenetic position of this bee using thre e mitochondrial genes, 16S ribosomal RNA(16S)and cytochrome oxidases subuni t 1 and 2 (CO1 and CO2). The earlier suggestion that A. nuluensis is closel y related to A. cerana was supported. We showed that this honeybee may deri ve from an isolated population of honeybees that colonized Borneo during Pl io-Pleistocene glaciations. Based on the divergence rate for silent sites o f mtDNA (2.3% per Ma), the population division between A. nuluensis and A. cerana in Borneo occurred between 0.5 Ma (from 16S) and 2.4 Ma (from CO1). Large inconsistencies in the application of CO2 in the phylogenetic analysi s of Apis were found. Geographic radiation of the eastern hive bee, Apis ce rana, occurred in unison with divergence, which led to the speciation of Ap is nuluensis.