Subfamily FORMICINAE
Tribe CAMPONOTINI

Camponotus(Tanaemyrmex) castaneus (Latreille) 

Camponotus castaneus, full face view of major. Notice the lack of erect hairs on the gena (compare to C. americanus). (click image to enlarge)
Camponotus castaneus, profile view of major worker (click image to enlarge)
Camponotus castaneus queen profile
Camponotus castaneus, profile view of male (click image to enlarge)
Camponotus castaneus, profile view of alate female (click image to enlarge)

Introduction
Ants in the genus Camponotus are collectively known as carpenter ants because some species nest in wood, including man-made structure. This genus includes some of the largest and most common ants in the world, and they are found in all biogeographical regions (Bolton, 1995).  More than 900 species of Camponotus are known worldwide, with 50 species reported from the United States (Hanson and Klotz, 2005), and 20 species found east of the Mississippi River (Deyrup, 2003; Smith, 1979). 

Species in this genus are variable in size with workers ranging in size from 3 to 15 mm or more in length and queens (also referred to as females) of some species attaining a length of 19 mm or more. Many species are polymorphic. Workers have a 12-segmented antenna that lacks an apical club. Antennal fossae do not touch the posterior border of the clypeus. Ocelli are not present on the heads of workers. The workers of most species have an indistinct metanotal suture between the promesonotum and the propodeum, although this suture is present in C. sexguttatus and some members of the subgenus Colobopsis.  Those species that lack the obvoius and deep metanotal suture have the shape of the alitrunk in a smoothly curved arc (as seen in profile). 

Identification
C. castaneus is in the subgenus Tanaemyrmex, and differs from the other carpenter ant subgenera by having a median carina present on the clypeus, however, this character is not very evident in this particular species. Camponotus castaneus is a large reddish colored carpenter ant (7-10 mm overall length). This species is very similar to C. americanus Mayr, but differs in that it is usually concolorous red to reddish brown and lacks erect hairs on the cheeks. C. americanus has a darker head (often approaching black) than the rest of the body and has erect hairs on the cheeks (best seen in major workers).

Biology and Economic Importance
This species nests in rotting logs and stumps, exposed soil, or in soil under objects. It is not considered to be a serious pest of wood products, though they are sometimes encountered in houses or other structures. However, they usually only enter buildings to search for food, rather than to nest in them. We have collected alates in early May through mid June and in September.

Distribution

Literature Cited

Links
AntWeb Images

Discover Life Images