Temnothorax schaumii

Modified from Mackay (2000): This species nests in the bark of living trees, in branches, logs and oak galls of trees. It occurs in many habitats that range from from desert canyons in trees, to grasslands, to shaded deciduous forests. Smith (1924) found this to be the most common Temnothorax in Mississippi and Wesson and Wesson (1940) found this species to be common in oak trees in Ohio.

Identification
Mackay (2000) "These ants have 11-segmented antennae and are usually concolorous dark brown, but are occasionally concolorous yellow. The head is nearly completely covered with fine striae, which merge with the dense punctures. Occasionally there is a central strip, which is partly free of sculpture and somewhat shining. The top of the mesosoma is mostly punctate, with a few striae, the side of the mesosoma has numerous striae with punctures between them. The propodeal spines range from tiny angles to small spines, which are dull and rounded. The petiole and postpetiole are punctate and the node of the petiole is weakly truncate, with round edges.

The 11 segmented antenna and tiny propodeal spines separate this species from all other species with 11 segmented antennae in the subgenus, except Temnothorax whitfordi. It can be easily distinguished from Temnothorax whitfordi as the head and pronotum are predominantly punctate (predominantly smooth and shining in Temnothorax whitfordi, but the pronotum may be punctate as in Temnothorax schaumii). The punctures on the pronotum of Temnothorax schaumii are fine and completely cover the surfaces, whereas in Temnothorax whitfordi they are coarse and do not densely cover the surface. The small spines separate it from the others in the schaumii species complex."

Distribution
United States. Kansas, Indiana, Iowa, Missouri, Oklahoma, Texas, Arkansas, Louisiana, Illinois, Kentucky,Tennessee, Alabama, Mississippi, Ohio, Pennsylvania, Massachusetts, New Jersey, Washington D. C., West Virginia, Virginia, North Carolina, South Carolina, Georgia.

Habitat
Ranges from from desert canyons in trees, to grasslands, to shaded deciduous forests

Abundance
common to abundant

Texas
Wheeler (1903) in notes about a Temnothorax schaumii synonym T. fortinodis:

"I have found only a single colony of this form at Austin. This had taken up its abode in an abandoned gall of Holcaspis cinerosus Basset on the live-oak (Quercus virginiana). It contained 143 workers, a single deiiJated queen and 35 larval in different stages. The latter were white and not greenish like the larval of L. obturator which inhabits the same kind of galls. The entrance to the fortinodis nest was a small round hole with much worn edges, evidently the modified exit of some parasite on the Holcaspis."

Nomenclature

 *  schaumii. Leptothorax schaumii Roger, 1863a: 180 (w.) U.S.A. Mayr, 1886d: 451 (m.); Wesson, L.G. & Wesson, R.G., 1940: 95 (q.); Wheeler, G.C. & Wheeler, J. 1960b: 23 (l.). Combination in L. (Myrafant): Smith, D.R. 1979: 1394; in Temnothorax: Bolton, 2003: 272. Senior synonym of fortinodis, gilvus, melanoticus: Creighton, 1950a: 271. See also: Wheeler, W.M. 1903c: 232; Mackay, 2000: 403.
 * fortinodis. Leptothorax fortinodis Mayr, 1886d: 452 (w.q.) U.S.A. Combination in L. (Myrafant): Smith, M.R. 1950: 30. Subspecies of schaumii: Wesson, L.G. & Wesson, R.G., 1940: 96. See also: Wheeler, W.M. 1903c: 233. Junior synonym of schaumii: Creighton, 1950a: 271.
 * gilvus. Leptothorax fortinodis var. gilvus Wheeler, W.M. 1903c: 235 (w.q.) U.S.A. Junior synonym of schaumii: Creighton, 1950a: 271.
 * melanoticus. Leptothorax fortinodis var. melanoticus Wheeler, W.M. 1903c: 235 (w.q.) U.S.A. Wesson, L.G. & Wesson, R.G., 1940: 94 (m.). Subspecies of fortinodis: Buren, 1944a: 287. Junior synonym of schaumii: Creighton, 1950a: 271.

Worker
2.5 Millim. lang, rothlich gelb, Hinflerleib an der Spitze etwas braunlich; die abstehenden Harchen sind keulenformig, kurz wie bei corticalis. Fuhler eilfgliedrig, ganz gelb. Mandibeln 4 – 5 zahnig, sehr undeutlicb gerunzelt. Clipeus ohne glanzenden Langseindruck. Kopf schwach langs gerunzelt, seitlich und hinten fein verworren oder fingerhutartig punktirt, schwach glanzend. Thorax dem von corticalis ganz ahnlich, oben ohne irgend einen Quereindruck, fingerhutartig punktirt, wenig glanzend, hinten in 2 kurze, an der Basis breite, 3-eckige Zahuchen endend. Stielchenglieder wie gewohnlich, das erste unten nit einem zahnformigen Vorsprung. Abdomen glatt, glanzend, Schienen onbehaart.

(Wheeler 1903) Length 2.5-2.75 mm, Mandibles 5-toothed. Clypeus convex witho:ut median impression; its anterior border rather straight. Antennre 11-jointed; scape reaching hardly to half way between the eye and the posterior angle of the head, funiculus with a distinctly 3-jointed club; first funicular joint almost as long as joints 2-5 together; joints 2-7 distinctly broader than long; terminal joint fully as long as the two preceding joints. Thorax rather short, flattened dorsally and laterally, broader in front than behind, with distinct and rather sharp humeral angles, and with a constriction at the mesoepinotal suture. Epinotal spines very short, dentiform, not longer than broad at their bases. Petiole seen from above oblong, 1 ½ times as long as broad, its sides parallel except at the peduncle which is narrower; in profile the anterior dorsal slope is concave and about the same length as the straight or somewhat convex posterior slope; ventral surface with a distinct tooth directed forward. Postpetiole scarcely half again as broad as the petiole, distinctly broader than long, oblong, with distinct though rounded anterior angles. Its dorsal surface is evenly semicircular in profile. Gaster of the usual shape, with small but distinct anterior angles.

Clypeus with sharp longitudinal rugae, two of which, near the middle, are more prominent than the others. Mandibles with distinct longitudinal rugae. Head, clypeus and mandibles with a silky luster, the first traversed by fine parallel rugae separated by rows of foveolate punctures, which are clearest in certain lights on the posterior lateral surfaces and cheeks. Thorax, petiole and. postpetiole opaque, covered uniformly with foveolate punctures. Gaster smooth and shining.

Hairs moderately numerous on the body, white, erect, clavate; short on the head and thorax, much longer on the gaster and of intermediate length on the pedicel. Hairs on the antennae and legs minute, non-clavate, appressed.

Yellowish-red, the edges of the mandibles black. Gaster in some specimens dark-brown thcroughout, in others yellow or with much of the base of the first segment yellow. Antennae and legs yellow, club and sometimes also the scape of the former, infuscated.

Male
(Wheeler 1903) Length 3.2 mm: Mandibles dentate, touching each other with their blades. Antennae 12-jointed, scape about as long as the first three joints of the funiculus together; funiculus from the second joint to the end of uniform thickness, filiform; second joint a little shorter than the third, shorter, in fact, than any of the succeeding joints. Instead of spines or teeth, the epinotum bears two indistinct elongate swellings. Radial cell of wings short and closed.

Mandibles rather smooth and shining, with scattered punctures near their inner edges. Clypeus moderately shining and very delicately longitudinally rugose. Cheeks and region between antennal insertions and eyes sharply striated longitudinally; front with delicate longitudinal rugae; vertex finely reticulate punctate. Thorax rather smooth and shining, median and posterior portions of mesonotum finely longitudinally rugose and in part obliquely. Petiole, postpetiole and gaster smooth and shining.

Pilosity sparse, tibim without suberect hairs.

Blackish-brown, pedicel and gaster darker. Mandibles, antennae except the brown scape, joints of legs, tarsi, and in part also the joints of the pedicel, yellow or reddish-yellow. Wings clear, hyaline.

Type Material
As reported in Mackay (2000) "The types could not be located in Roger's collection (Museum fur Naturkunde Zentralinstitutder Humboldt-Universitiitzu Berlin), and probably no longer exist. "

Type Locality Information
Pennsylvania

Etymology
Commemorative. For the collector of the types, Prof. Schaum.

Additional References

 * MacKay, W. P. 2000. A review of the New World ants of the subgenus Myrafant, (Genus Leptothorax) (Hymenoptera: Formicidae). Sociobiology. 36:265-444.
 * Roger, J. 1863. Die neu aufgeführten Gattungen und Arten meines Formiciden-Verzeichnisses nebst Ergänzung einiger früher gegebenen Beschreibungen. Berliner Entomologische Zeitschrift. 7:131-214.
 * Smith, M. R. 1924. An annotated list of the ants of Mississippi (Hym.). Entomological News. 35:47-54.
 * Wesson, L. G. and R. G. Wesson. 1940. A collection an ants from southcentral Ohio. American Midland Naturalist. 24:89-103.
 * Wheeler, W. M. 1903. A revision of the North American ants of the genus Leptothorax Mayr. Proceedings of the Academy of Natural Sciences of Philadelphia. 55:215-260.