Tierra de Oro Laboratory

Physiology and Ecology in the Pinyon-Juniper Savanna

Velvet Ants: Dangerous Beauties

Velvet ants are commonly observed wandering the landscape this time of year. Although referred to as ants, they are wasps in the family Mutillidae. Then again, ants are really a family of wasps, so one can quickly get mired in details by being picky about common names.

Males are fully capable of flight, and look very much like other wasps, whereas females are flightless. Both males and females feed on nectar. The fact that they are earthbound, coupled with their fuzzy and often colorful appearance makes these insects easy to recognize.

The above subtitle “Dangerous Beauties,” refers to two aspects of the ants’ biology.

First, both species described below are ectoparasitoids of ground-nesting bees. That is, their larvae develop attached to the larvae of their hosts, and ultimately kill them.

The second reason for calling them dangerous is because of the females’ powerful stings. Being stung is apparently excruciating to humans, and is an effective defense against most predators. Velvet ants use bright colors and stridulating noises to warn potential predators of the hazards.

Below are two species from closely related tribes of velvet ants. They share common features of velvet ants (e.g., strong stings and parasitic reproduction), but differ in some aspects of physical appearance, behavior, behavior and natural history.

Velvet Ants

The common velvet ant, Dasymutilla vestita, is brightly colored and active during the day.

Velvet ant, Dasymutilla vestita, crossing the street near the lab. 5/24/26.

The females appear as colorful fuzzballs wandering around in western North America. Generally some combination of black, red, and/or yellow.

Nocturnal Velvet Ants

Nocturnal velvet ants are seen more rarely. They are generally smaller, more drably colored, and, unsurprisingly, nocturnal. You can click the photos for larger views.

Nocturnal velvet ant from pitfall trap. 8/14/25.
Another view of the same insect. 8/14/25
Photomicrograph of the same velvet ant as above. Note sting at end of abdomen. Photo 5/23/26 of female collected 8/14/25.

The above nocturnal velvet ant is in the genus Odontophotopsis, but I have not been able to identify the species as yet.

A few references

Gall et al., (2018) The indestructible insect: Velvet ants from across the United States avoid predation by representatives from all major tetrapod clades. Ecol Evol 8:5852-5862.

Velvet Ants, Mutillidae (Insecta: Hymenoptera) https://ask.ifas.ufl.edu/publication/IN717 (note Florida focus)

Comments

Leave a Reply

Your email address will not be published. Required fields are marked *