Diversity of Host Plants in Association With Weaver Ants, Oecophylla Smaragdina (Hymenoptera: Formicidae) With Respect to Colony Inhabitation, Behavior, Preference and Coexistence From South Kamrup, Assam, N.E. India.

Myrmecophytism is biologically interesting, least studied plant–ant association occurring in both tropical and sub-tropical regions over large genera belonging to different plant families. Various host plant species associated with weaver ant (Oecophylla smaragdina) are predominantly distributed in different parts of India with comparatively few species distributed in N.E. India particularly in Assam. Common host plant species where Oecophylla smaragdina colonizes are Glycosmis pentaphylla (Rutaceae), Artocarpus heterophyllus (Moraceae), Croton joufra (Euphorbiaceae), Mangifera indica (Anacardiaceae), Litchi chinensis (Sapindaceae), Shorea robusta (Dipterocarpaceae), Citrus auruntifolia (Rutaceae), C. grandis (Rutaceae) etc. Colony inhabitation of O. smaragdina was found in nearly 23 host plants under 17 families namely, Dioscoreaceae, Moraceae, Sapindaceae, Myrtaceae, Fabaceae, Rubiaceae, Asteraceae, Anacardiaceae, Cucurbitaceae, Rutaceae, Dipterocarpaceae, Piperaceae etc. of which highest number of species (4 in number) is represented from the family Rutaceae followed by representation of single species from various families. Occurrence of colony inhabitation of O. smaragdina in Mangifera indica and Elaeocarpus floribundus is observed to be highest for most of the months of the year and some existing nest are abandoned by the ants. In some other species, the occupancy of O. smaragdina ranges from 3 to 8 months. These ants have exceptional nest-building skills using leaves of host plants and uses larval-silk as a binding agent for making nest. This study is the first of its kind from this region in regard to diversity of host plant species associated with weaver ants. It was observed that Oecophylla smaragdina build nests more abundantly in Mangifera indica compared to other plant species. The nests build by O. smaragdina are nearly globular, oval, cigar shaped or sometimes irregular in shape using the leaves of different sizes and maturity. Out of 23 host plant species recorded with respect to nest construction, 16 species are trees, 3 species are climbers, 3 species are shrubs and 1 species is a herb. The nest size varies depending upon the plant species. The nests are constructed at a different height from the ground depending upon the habit of the host plant. The ants utilize about 5-25 leaves for making nest having specific number of chambers for accommodating queen, broods, worker ants and diverse foods. Depending upon the size of the nest, the number of worker ants, pupae, larvae are variable. Studies also show that the active foraging and nest building activity of O. smaragdina is at 18-27 °C which declines notably with the rise in temperature