Stings and squeaks: The diversity of Mutillidae on Fairchild Air Force Base

Velvet ants, as they are colloquially known, are wasps in the family Mutillidae. They are a highly sexually dimorphic group, with females being entirely wingless while males in almost all species possess wings. Mutillids are inarguably most famous for the very painful sting of females. These insects are parasitoids of other ground nesting Hymenoptera, primarily bees, and less commonly other insect taxa. Although they are most often found in the tropics and subtropics of the world, North American deserts are also home to a high species diversity. While states in the southwest, such as Arizona, boast as many as 200 species, many other states have little data on mutillid diversity. Washington State only has 20 species on record as of 2024 data, but a more in depth look at museum specimens and the results of a survey on Fairchild Air Force Base just west of Spokane have helped to bolster that number. Despite only comprising and area of land less than 1 square kilometer, we found a surprising diversity of mutillid species on Fairchild Air Force Base, further reinforcing that the area has been historically under sampled and more work needs to be done to document Washington State's insect fauna.