Excerpts from Jim Conrad's
from the May 5, 2013 Newsletter issued from the Frio Canyon Nature Education Center in northern Uvalde County, southwestern Texas, on the southern border of the Edwards Plateau, USA
ANT MIMICKING SPIDER
The ant navigating among my arm's hairs caught my attention with its black-and-red abdomen. In general, ants aren't two-colored. Also, the shape wasn't quite right. Not being able to see too well and suspecting something interesting here, I snapped the picture shown below.
The moment that image came onto my laptop monitor I knew that my ant wasn't an ant, if for no other reason than that it had eight legs, and therefore wasn't even an insect. It's an ant-mimicking spider. The picture at the top of this page takes a closer look at the head region -- the cephalothorax -- making the point better.
At first I identified the spider as Peckhamia americana, an ant-mimicking spider known to occur in Texas. However, Tim Manolis, who illustrated the new book Field Guide to the Spiders of California and the Pacific Coast States, graciously wrote saying that we have SARINDA HENTZI. He says, "The most noticeable difference between these two genera of ant-mimics involves the front legs. In Sarinda, the front legs are long and very thin and waved around to mimic antennae: In the genus Peckhamia, the front legs are short (shorter than the second pair of legs) and thick. In Peckhamia, the SECOND pair of legs are waved around like antennae." Tim adds, "Pretty amazing that these two un-related genera of jumping spiders have evolved independently to look like ants and yet use different legs to mimic the waving of antennae!"
Sarinda hentzi occurs thoughout much of the US, especially the southern states, south through Mexico and Central America.
Last December we profiled the Texas Bow-legged Bug, which was an ant mimicking bug (http://www.backyardnature.net/n/a/bow-leg.htm ) and now here's another ant mimicker. If there's a lesson here, I suppose it's that you can cut down on the number of predators chasing you -- or sneak up more easily on your own prey -- if you look like an ant.