Most of them are smaller than pavement ants (about 2 mm) but there's more variation in size, with the bigger workers just as large or larger than T. caespitum.
What made me suspect that they weren't just normal pavement ants is the color variation- to a varying degree, some of the workers are paler and more reddish than their counterparts. In person, they really stand out and look like a different species of ant than their counterparts.
![](http://i.imgur.com/S3IOecY.jpg)
![](http://i.imgur.com/r8KnjPF.jpg)
Edited by Salmon, July 7 2016 - 4:12 PM.