myrmecophil's Identifications

Dead Nomamyrmex army-ant workers collected from a mound of the leafcutter ant Atta texana. The workers here are under ethanol, and images are therefore somewhat blurry.

Nomamyrmex are specialist predators of Atta, but they prey also on other ant species. This here is most likely Nomamyrmex esenbeckii, but I identify only to genus because there have been suggestions that Nomamyrmex hartigii may also occur in south Texas. In my nearly 25 years surveying ants in south Texas, I have seen live Nomamyrmex only once, 9 years ago at the Mesquite Trail at the visitor center at Laguna Atascosa NWR (near the cemetery at the northern loop of the Mesquite Trail; 28. November 2013, ≈12:15PM; UGM131128-01) .

I recently started to search for dead Nomamyrmex on Atta texana mounds that look disturbed and "disheveled", perhaps because they were recently raided by Nomamyrmex. This here is the first find of Nomamyrmex since I started to search the ground on top of such "disheveled" Atta mounds more closely. The dead workers here were dry, and half-embedded & baked into the top soil (sand), so the Nomamyrmex raid on this Atta mound must have occured a while ago, sometime before the last rain here.

See also my below comment added in Feb.2023: "I finally found the time to ID to species, using a microscope and the Watkins 1977 key: Post-occipital sulcus present, therefore esenbeckii"

observation UGM220314-16
elevation 14 meter