Abstract
Tropical dry forests are among the most threatened and least studied terrestrial ecosystems globally, supporting high
levels of endemic biodiversity despite their characteristically harsh seasonal climate. Ants (Hymenoptera: Formicidae)
are dominant components of tropical dry forest soil and litter communities, performing critical ecosystem functions
including seed dispersal, soil aeration, and prey regulation. This study presents a systematic survey of ant diversity
across tropical dry forest sites in the Deccan Plateau of India (Telangana and Karnataka), the Caatinga of northeastern
Brazil, and the seasonally dry forests of Oaxaca, Mexico, using standardised pitfall trap, winkler litter extraction, and
baiting protocols at 54 sites surveyed during both wet and dry seasons. A total of 284 ant species belonging to 58 genera
and 11 subfamilies were documented across all sites. Species richness was highest in the Brazilian Caatinga sites (mean
84.2 species per site) and lowest in the Indian Deccan sites (mean 48.6 species per site), consistent with the latitudinal
diversity gradient. Myrmicinae was the dominant subfamily at all sites (42.6% of species), followed by Formicinae
(18.3%) and Ponerinae (14.1%). Functional guild composition differed significantly among regions, with generalised
Myrmicini dominant in Indian sites and specialist army ant foragers more prominent in Neotropical sites. Habitat
disturbance gradient analysis reveals that selective logging reduces ant species richness by 28.4% and dramatically
alters functional guild composition. An updated key to Indian tropical dry forest ant genera is provided.