A natural history account of Megalomyrmex ayri Brandão, 1990 (Hymenoptera: Formicidae: Myrmicinae)

The ant genus Megalomyrmex Forel, 1885, has 45 valid species and is spread across the entire Neotropical region. Megalomyrmex species have been studied for decades and there are many rich natural history accounts that describe various details, including symbionts and unusual reproductive strategies. Natural history traits such as lifestyle have been used to help delimit Megalomyrmex species and the four species groups (i.e., Leoninus, Modestus, Pusillus, and Silvestrii), but recent findings suggest well-sampled comparative studies coupled with revisionary taxonomy are still needed. We report observations of the natural history of the Megalomyrmex ayri Brandao, 1990, regarding diet, nesting habits, abundance, distribution, and reproductive strategy. The sampling was conducted in a Terra Firme Forest, in the municipality of Itaituba, state of Para, in the Tapajos River region of the Brazilian Amazon. Our observations reduce knowledge gaps about the lesser known Megalomyrmex species, and are essential for an understanding of the evolutionary history of the genus.