Subfamily MYRMICINAE
Tribe PHEIDOLINI

Aphaenogaster carolinensis Wheeler

Aphaenogaster carolinensis, profile view of worker. Propodeal spine length is variable and the spines pictured above are at the shorter end of the scale. The contrasting light yellowish brown legs are typical for specimens in our area (click image to enlarge).
Aphaenogaster carolinensis, full face view of worker (click image to enlarge).
Aphaenogaster carolinensis, profile view of worker (click image to enlarge) .
Aphaenogaster carolinensis, profile view of dealate queen. Notice the smooth mesopleural area (click image to enlarge).
Aphaenogaster carolinensis, full face view of dealate queen (click image to enlarge).

Introduction
Ants in the genus Aphaenogaster are medium sized to large, slender with long legs and antennae, usually have propodeal spines (a few species lack spines), have 12 segmented antennae with the last 4 segments forming a weak club. The genus is widespread in North America and species nest in rotting wood, under bark, and in soil.

Identification
According to Umphrey (1996) it is very difficult to distinguish this species from A. N19, a form which he described in his manuscript. However, since he has not named any of these forms as species, I am simply calling our species A. carolinensis for the time being. It is likely that there are a couple of species mixed in there. Workers are variable in size, color, and length of the propodeal spines. Typical specimens in this area are light to darker reddish brown with yellowish brown legs and coxae; heads narrowed and much longer than wide; and prododeal spines short and usually directed backwards toward the gaster. The mesopleural area of the queen is smooth and is quite different from A. fulva, which has a striate mesopleuron. Workers of A. carolinensis differ from A. fulva by having shorter propodeal spines, generally lighter color, lighter colored legs and coxae, forecoxae not being obviously striate, and the mesonotum either not being raised above the level of the pronotum, or if so, then lacking a welt or depression as seen from front to back (or back to front). Both A. carolinensis and A. fulva are often found in the same habitats, although A. fulva tends to nest in rotting wood.

Biology and Economic Importance
Aphaenogaster carolinensis is a very abundant ant in the Southeast in forested areas where it usually nests in the soil in relatively small colonies. Alates have been collected in early to mid June.

Although this species has the potential to sting, it is unlikely to pose any serious threat due to its non-aggressive behavior. I have handled thousands of this species and never received a sting, even when they were crawling all over me! Due to its abundance in the landscape, it could be an occasional nuisance pest in the home as workers forage for food.

Distribution
In the Southeast, this species has been found in AL, AR, FL, GA, LA, MS, NC, TN.

Literature Cited
Umphrey, G. J. 1996. Morphometric discrimination among sibling species in the fulva-rudis-texana complex of the ant genus Aphaenogaster (Hymenoptera: Formicidae). Canadian Journal of Zoology 74: 528-559.

Links
AntWeb Image
Discover Life Images