Stenamma meridionale

From Smith 1957: The only collections of meridionale made directly from colonies were those of Mary Talbot in the Droste Woods in St. Charles County, Missouri. She described the woods as a small, mixed oak-hickory woods, with large red and white oaks predominating. There was a great variety of other trees such as linden, elm, sycamore, maple, and sassafras. The collections were made in a pawpaw thicket occupying a gentle slope from a ridge to a small stream in the center of the woods. The trees overhead allowed moving patches of sunlight but did not form the continuous deep shade of beech-maple woods. There were scattered shrubs of buck brush, elderberry, sumach, etc., with the herb layers consisting of spring blooming flowers such as spring beauty, mandrake, dentura, and red trillium. The ground cover had a fairly heavy leaf covering mixed with a litter of twigs, acorns, hickory nuts and decaying branches. The soil was very dark and loose for three or four inches, then it became progressively compact and light colored until below six or seven inches it was a very hard-packed clay. Colony 48-2 was collected-November 10, 1948, from two chambers in which the ants were hibernating" in hard clay in depths of 10 and 15 inches. This colony was found when the air temperature was 43° F "and the soil temperature 52° F. In the 10 inch chamber both workers and larvae were found, in the 15-inch chamber only a few workers. Although the ground was dug to a depth of 21 inches, no other immature stages or adults were found. The total content of the nest was 19 workers and 36 medium to large larvae, but no pupae, females, "or males. This may not have represented the entire colony. The second colony, 52-12, was found October 6, 1952, in a chamber 13 inches deep which looked like a horizontal crack in the dry, hard clay. There had been no cold weather and the ants were still foraging in the woods. The air temperature at this time was 73° F, and the soil temperature 58° F. From the chamber were taken 11 workers and one deal ate female, four have but no eggs, pupae, winged females or males. In localities in other states where collections were usually made with Berlese funnel, single collections usually produced only from 1-13 workers with occasionally a dealate female. These individuals were largely taken from leaf mould, ground cover or top soil, mostly, if not entirely, in the woods. At this time- we do not know the maximum size of colonies, the diversity of the nesting habits nor the month or months of the year in which males and winged females are produced.

Talbot (1957) added some additional published information to that she supplied to Smith. This information was part of a study where she excavated soil during the cooler months of the year, in a Missouri woodland, on order to survey ant nests. "Stenamma meridionale was found only once on the plots and once previously. The two colonies overwintered larvae, as did the other Stenamma. One occupied a chamber thirteen inches deep, and one had two chambers, ten and fifteen inches deep, in the hard, yellow clay. The colonies collected were small, being made up of sixteen and 55 individuals of which eleven and nineteen were workers."

Identification
Stenamma meridionale workers can be distinguished by the following characters: Large size, 3.4-4 mm; large eyes, which have 8-10 ommatidia in their greatest diameter; pronounced mesoepinotal constriction, which is often as much as 0.15 mm in its greatest length and from 0.05 to almost 0.10 mm in depth; the posteriorly sloping base of the epinotum; the long, finger-like epinotal spines; and the anteroposteriorly compressed petiolar node, which when viewed from above and behind is subrectangular and has a straight or weakly emarginate superior border.

Smith 1957

Distribution based on Regional Taxon Lists
Nearctic Region: United States.

Range
Virginia, Missouri, and Illinois south to South Carolina and Arkansas. The most northern locality from which this species has been collected is Oakwood, Vermilion County, Illinois, which is slightly above the 40th degree of latitude.

Smith 1957

Nomenclature

 *  meridionale. Stenamma meridionale Smith, M.R. 1957b: 169, pl. 4, fig. 15 (w.q.) U.S.A.

Type Material
Described from individuals collected from two colonies by Mary Talbot. The holotype and 15 paratype workers from colony No. 48-2 collected 11-10-48 and a wingless female and 11 paratype workers from colony No. 52-12 collected 10-6-52. All of these have been placed in the U. S. National Museum under U.S.N.M. No. 62392.

Type Locality Information
Droste Woods, St. Charles County, Missouri.

Etymology
Descriptive. Presumably Smith felt this species was relatively restricted in its latitudinal range, meridional L. = southern

Additional References

 * Talbot, M. 1957. Populations of ants in a Missouri woodland. Insectes Sociaux. 4:375-384.
 * Smith, M. R. 1957. Revision of the genus Stenamma Westwood in America north of Mexico (Hymenoptera, Formicidae). American Midland Naturalist. 57:133-174.