MtDNA variation in Apis cerana populations from the Philippines.

The cavity-nesting honeybee Apis cerana occurs in Asia, from Afghanistan to China and from Japan to southern Indonesia. Based on morphometric values, this species can be grouped into four subspecies: A. c. cerana, A. c. indica, A. c. japonica and A. c. himalaya. In order to analyse the geographical variability of A. c. indica from the Philippine Islands, 47 colonies from different locations in three of the larger islands (Mindanao, Luzon and Palawan) and four of the Visayan Islands (Panay, Negros, Cebu and Leyte) were studied. Genetic variation was estimated by restriction and sequence analysis of PCR-amplified fragments of the tRNAleu-COII region. We found four different haplotypes, Ce1, Ce2, Ce3 and Ce4, that discriminate among the bee populations from different islands. The Ce1 haplotype is present in Mindanao and Visayan Islands, Ce2 is restricted to Luzon, and both Ce3 and Ce4 are only present in Palawan. Phylogenetic analysis of the sequences shows a great intraspecific variability, is in accordance with the geological history of these islands and partially agrees with some previous morphological and molecular studies.