Morphometrics of the dwarf honey bee Apis florea show biogeographic differentiation across India

The Asian dwarf honey bee (Apis florea) is a relatively small honey bee, nests in the open with single combs attached to tree branches, and inhabits areas uninhabitable to other Apis species. A. florea is one of few honey bees in the genus to have remained unmanaged by beekeepers across Asia. Because A. florea has not been bred for specific traits or transported intentionally across continents like managed Apis species, populations of A. florea should offer insight into natural adaptations of honey bee populations to diverse climates. We use morphometrics to examine which environmental factors correlate with morphological differences between populations of A. florea surveyed across India. The surveyed populations show a trend of increased wing size going from the equator to the north. The populations also vary in Cubital Index, a wing venation measurement often associated with subspecies differentiation, and this variation is correlated with minimum temperature of the coldest month. Taken together, these findings show that A. florea differs morphologically across a temperature gradient in India and support future work towards understanding biogeographic patterns in this understudied species of honey bee.