More than 55 species of velvet ants inhabit Colorado and at least one or another of the velvet ants can be found in most areas of the state with the exclusion of higher elevations. Lower elevations of open fields of prairie short grass in both eastern and western Colorado are common habitats in which to find velvet ants. Contrary to their name, velvet ants are actually wasps. The females are flightless and may be found moving rapidly across the soil in search of nests belonging to solitary bees and wasps in which to lay her eggs. Their body resembles a worker ant that is covered in dense bristly hairs. Females have stingers that pack a painful sting when utilized. This powerful sting has led to another common name of “cow-killer” although there is no truth behind the name. Males are winged and usually larger in size than females. Unlike the females, males only have a false stinger and although they will bluff sting, they are not capable of an actual sting. Velvet ants in general are not aggressive and are quick to retreat when disturbed. Size varies depending on species and gender, ranging from 5-20mm in length. Body hairs range from red, orange and yellows to black and white. Males’ coloring tends to be a bit more muted than females. Differences in body coloring and form make it difficult to identify genders of the same species. While some species have thick hairs covering a majority of their body, others have thinner more sparse hairs.
Males are commonly seen flying near the ground in search of females. After mating, females seek out the nests of ground dwelling solitary bees and wasps. Once located, the female velvet ant digs into the nest, locating the developing bees/wasps within. Eggs are laid on stages that have completed feeding and are preparing for pupation. The velvet ant mother will cut thought the host’s cocoon and lay and egg which upon hatching will consume the bee/wasp host. Velvet ants likely produce only one generation per year and spend the winter in the pupal stage within the tunnels of the bees/wasps on which they have fed. Adult velvet ants emerge in the late spring. As adults, both males and females feeding on nectar and pollen and are often more easily observed as they visit flowers such as milkweed to feed.