Main Characteristics of Rugose Harvester Ants

Physical Traits

• Rough or rugose harvester ants are a darker colored species with a very rough and wrinkled exoskeleton. Workers are dark brown to reddish brown, but you will see a yellow one occasionally. The rough harvester ant has a relatively broad head, with widely separated and coarse rugae, or ridges. The ants use their wide mandibles for harvesting and transporting scavenged food, as well as to bite a victim when imparting a sting. Rugose ants have a particularly nasty sting, according to zipcodezoo.com, which contains the most powerful insect venom documented in any insect.

Behavior

• Rugose harvester ants are foragers and scavengers. They are aggressive when confronted and employ an odd stance. The ants move with their abdomen curled up beneath them when patrolling; this posture increases when the ants are in defense mode. The ants do not forage on a regular basis; instead they follow seed and insect availability. Often the foraging coincides with an insect hatching, according to Navajo Nature, resulting in a more successful foraging excursion.

Feeding Habits

• Seeds snipped with the mandibles are the primary food for the rugose harvester ants. The ants husk the seeds within the nest and store them in underground chambers. Insects, scavenged or preyed upon when the ants are out on foraging excursions, are supplemental food in addition to the seeds. The ants' mandibles are the primary gathering tool, chopping stems and snipping seeds from grasses. They are also the main method for carrying food back to the nest.

Habitat

• The preferred habitat of the Rugose harvester ants is arid desert with a pebbly soil, which blankets most of the southwest states' desert areas. Arizona, Texas, New Mexico, California and even Oklahoma and Colorado are home to this species. Rugose harvester ants build nests in the ground that can run over a meter deep. A central shaft leads to a large number of chambers, often over a dozen or more. Course gravel may mark the opening to the nest, and usually just a single opening for the colony exists to the nest's underground chambers.