Apis cerana from Myanmar (Burma): Unusual distribution of mitochondrial lineages

We investigate genetic variation and biogeography of the cavity-nesting honey bee, Apis cerana, F. in Burma, to add them to the larger picture of A. cerana biogeography in Asia. Non-coding regions of mitochondrial DNA (mtDNA) of 23 colonies collected from 12 localities are sequenced to identify their genetic lineages. Six haplotypes were found (Japan1, Nepal1, ThaiS1, BurmaN1, BurmaN2, and BurmaN3) belonging to two A. cerana mtDNA lineages: Mainland Asian and Sundaland. The Mainland lineage was found in most parts of Burma except the Southeast, where a Sundaland population was found. Studies in Thailand suggested that the Sundaland lineage was not found north of 10° 34' N; this study shows there is a Sundaland population in Burma at 19°-20° N latitude. We propose three hypotheses to explain the presence of the Sundaland lineage in Burma: (1) Burma Sundaland bees are a relict of a formerly more widespread Sundaland population; (2) Sundaland bees migrated to this part of Burma from the southern Thai-Malay peninsula; or (3) transportation by humans.