Current Distribution of Tiger Spiders (Genus: Poecilotheria), in Selected Sites in Sri Lanka

Abstract

Six species of Poecilotheria are currently recorded in Sri Lanka: Poecilotheria fasciata, Poecilotheria ornata, Poecilotheria subfusca, Poecilotheria uniformis, Poecilotheria smithi and Poecilotheria pederseni, the genus is widely distributed covering all geo climatic zones of the island. It has been found that, each species is restricted to a specific locality, no overlap with that of others being observed, a unique feature amongst this genus. The objective of the survey was to map the distribution of the genus Poecilotheria in selected study sites in Sri Lanka. The study was initiated in 2009 and continues to date. The capture and release method was used to identify Poecilotheria spp. distinguished by the ventral markings on leg I and leg IV. So far seventy-one sites covering all ecological zones have been surveyed. In three of the sites no species of Poecilotheria was recorded. Of the other 69 sites, in the Northwest, Southern, Eastern, Northern and Central Provinces, 112 sighting of Poecilotheria (P. fasciata - (61), P. ornata (18), P. subfusca (9), P. smithi (2), P. pederseni (7), P. cf regalis (10), P. cf hanumavilasumica (3)) were recorded. The survey recorded two poecilotherians which have not been described previously. They are likely to be new species. Most species were found in their specific microhabitats, such as bark peels, hollows in trees, etc. The most preferred trees being Drypetes sepiaria, Chloroxylon swietenia, Manilkara hexandra, in the Dry Zone, Cocos nucifera, Thespesia populnea, Ficus sp, Areca catechu in the Wet and Intermediate Zones, while distinct preference was observed for abandoned sheds, cracks in walls, crevices amongst rocks, in the Highland eco-zone.