Stigmatomma pallipes

Identification
The genus Amblyopone with 74 species world wide occurs in tropical and subtropical leaf litter, preying on arthropods. There are three species of Amblyopone in North America.

Amblyopone trigonignatha Brown 1949. This species is known only from a single specimen that was extracted from leaf litter with a Berlese funnel. It was found in Concord County, North Carolina.

A. oregonensis is found in British Colombia, Washington, Oregon, northern California and extends eastward into mesic areas of the Pacific Northwest.

Ambylopone pallipes found in the Eastern United States is not a common ant, but it can be discovered by turning over stones and searching carefully through rotten wood on the ground. These small, dark reddish-brown ants are about ¼ inch in length. The eyes are very small, with only one or two facets. There is a row of small teeth on the anterior margin of the clypeus and the mandibles are long and linear with a row of bi-dentate teeth on the inner margin. The petiole is broadly joined to the gaster.

Range
This primarily eastern species is widely distributed, occurring in most eastern states except in Maine and Pennsylvania where it has not yet been reported. This species distribution expands westward all the way to California and is found sporadically in the mountains of Arizona.

Habitat
The small colonies are most common in wooded areas where they are found in rotten logs and under stones. They prefer moist, cool habitats. Centipedes and beetle larvae appear to be the main food source. In New England these ants are often found nesting under rock walls.

Abundance
This ant species is seldom if ever abunndant. Due to their small colony size and nest location under rocks and in logs in forests, this ant species is difficult to find.

Biology
Colony size is small, often less than 20 to 50 workers. The workers are slow moving, and forage under ground and in rotten logs where they are difficult to find. The pupae are covered with a brown silk case that helps in identification in the field. The queen is worker-like and inconspicuous. The males and females mate during the late summer months.

Etymology
"Pale-footed” Primitive Ant

Foraging/Diet
The highly modified mandibles appear to be specialized for hunting centipedes. Predators of centipedes and beetle larvae in forest litter.

Colony Attributes
The colongy size is relatively small with often less than 50 workers.

Nesting Biology
Nest under stones and in old logs.

Reproduction
Single reproductive queen.

Behavior
Primitive social structure with no trophallaxis.

Associations with other Organisms
It is possible that Pyramica species are most often found under the same stone.

Queen




Taxonomy
Typhlopone pallipes Haldeman, 1844: 54 (w.) U.S.A. Emery, 1895c: 261 (q.m.); Wheeler G.C. & Wheeler, J. 1952a: 114 (l.). Combination in Amblyopone: Haldeman, 1849a: 201 (footnote); in Stigmatomma: Roger, 1863b: 20; in Amblyopone: Brown, 1960a: 169. [Stigmatomma pallidipes: Dalla Torre, 1893: 14, unjustified emendation.] Senior synonym of serratum: Mayr, 1886d: 439; of binodosus: Emery, 1895c: 261; of arizonense, wheeleri: Creighton, 1940b: 3; of montigena: Brown, 1949c: 84; of subterranea: Brown, 1960a: 169. See also: Whelden, 1958: 1; Traniello, 1982: 65.

Original Combination
Typhlopone pallipes Haldeman, 1844.