I returned to the location of my observation of this species (https://www.inaturalist.org/observations/42268155) from yesterday (April 15, 2020). I observed a number of individuals and was able to get better photos which show the dark legs and rear facing flange on the outer face of the frontal lobe.

I noted that these ants seemed to seek cover at any sign of movement from my approaching camera lens, diving into crevices or under debris (as shown in my previous photos 🙂), remaining motionless; however, persistence prevails ...