Tag Archives: crematogaster

A few weeks ago, I flipped a rock in western New York state, and found a cluster of Crematogaster ants.

There had already been a frost, and the ants were apparently using the rock as a warm place to huddle.

At first I was admiring the ants, and the orange-brown insect didn't really register. After all, we commonly see cockroaches that look a lot like that under rocks here in Phoenix. We have Turkistan roaches everywhere.

Then it dawned on me, I was in an old-growth field, at least 1/2 mile from a house. Plus, that area of rural western New York is not known for Turkistan cockroaches.

Could it be a myrmecophile cockroach? A few species of cockroaches are known to be myrmecophiles. In fact, Hocking (1970) had found found Blattella lobiventris with Crematogaster mimosae in acacia thorns (Holldobler and Wilson's The Ants).

This little insect also looks a little bit like the Eastern ant cricket, Myrmecophilus pergandei (see BugGuide images), although it seems to lack the enlarged back legs for jumping.

What do you think?

Here's an excerpt about cockroaches in ant nests from
Cockroaches: Ecology, Behavior, and Natural History

By William J. Bell, Louis M. Roth, Christine A. Nalepa

There is a story on the Internet of a myrmecologist (unfortunately unnamed) finding 10 species of ants, including army ants, while waiting for a flight at the Tucson, Arizona airport. I had two hours in Tucson on Saturday morning, so I wondered if I could do as well. For the next few days we'll see if I was up for the challenge.

The first ant I found was a worker of the genus Crematogaster, named for its lovely heart-shaped rear section or gaster. This cutie is Crematogaster opuntiae, a specialist often found feeding on the extrafloral nectaries of cacti. This particular cactus is a cholla, Cylindropuntia.

Although Crematogaster opuntiae workers are known for chasing herbivores away from cacti in defense of the extrafloral nectaries, they are also predators of other insects, such as termites.

For more information, try:

Charles H. Pickett and W. Dennis Clark. (1979).The Function of Extrafloral Nectaries in Opuntia acanthocarpa (Cactaceae) American Journal of Botany. 66(6):618-625.

Discover Life has a photograph of Crematogaster opuntiae raiding termites

Alex Wild also has some fabulous photographs

Finally, if your French is good, Fourmis et Cactus à Nectars Extra-Floraux