ABSTRACT
Honeybees are one of the most important productive insects primarily for producing honey and for ecosystem services by pollinating a range of plant species ensuing sustainable crop production and maintenance of plant diversity. The classification of Apis species has gained importance because of their economic, nutritional and ecological roles. Behavioral traits, honey yielding ability, temper and pollinating efficiency vary greatly among honeybee species. Of the ten commonly identified species of genus Apis, the giant tropical honeybee Apis dorsata and the Himalayan giant honeybee Apis laboriosa strikingly differ from other honeybee species in their behavior and ecology. Apis dorsata that shows a greater degree of nest site fidelity has gained the status of keystone species in the forest ecosystem owing to its crucial role in the sustenance of forest flora and fauna. They are known for their aggressive defense strategies and vicious behavior, particularly when disturbed. A. laboriosa nests on high-altitude inaccessible cliffs and can adapt to cold and low temperatures. A. laboriosa though initially considered as a subspecies of A. dorsata, but with substantive differences in drone morphology, distinct morphometric differences and performance, and ecosystems, they have been unequivocally distinguished as two distinct species. This is also envisaged from the comparative genomics analysis that indicated stronger positive selection (2.5 times more genes) and more recent duplication/loss events in A. laboriosa genome than in the A. dorsata genome. Phylogenic relationship, evolutionary dynamics and adaptations of A. laboriosa is also compared with the Apis dorsata. Knowledge on the species composition and population structure of giant honeybees is vital for conserving the keystone species.
