Temnothorax pergandei

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Biology
Wheeler (1903) The type specimens of this fine species were taken by Mr. Pergande in a nest of Monomorium minutum Mayr var. minimum, and it was supposed that the Leptothorax was a guest in the nests-of the Monomorium, but Forel, who observed the species in North Carolina, showed that this was altogether an exceptional case. He found L. Pergandei living" in independent formicaries, in the moss of woods or in the earth of meadows, like the ordinary species of Leptothorax" (Ann. Soc. Ent, de Belg., Tome XLV, 1901,pp. 389-398). In Texas I have had ample opportunity to observe the habits of this ant, especially in the neighborhood of Austin, where it is found making its nests in very sparsely grassy spots among the mesquite and Opuntia thickets. The nests can be found only by carefully tracking foraging workers, as the entrance is a small hole often concealed under a dead twig or a tuft of grass roots. The colonies are hardly more populous than those of other species of Leptothorax. The winged -forms appear during the last week in April and the first week in May. The workers run about on the soil in the hot sun as fierce hunters of small insects (Aphids, minute Heteroptera, etc). As they are extremely pugnacious even toward individuals of the same species from other nests, and as I have never found them nesting with Monomorium minimum, though this species is very common in the same localities, I believe, with Forel, that Pergande's observation must be quite exceptional or may even involve some misinterpretation.

Original Combination
Leptothorax (Dichothorax) pergandei Emery, 1895c: 323, pl. 8, fig. 13 (w.) U.S.A. Wheeler, W.M. 1903c: 257 (q.m.); Wheeler, G.C. & Wheeler, J. 1960b: 23 (l.). Combination in Temnothorax: Bolton, 2003: 272. Senior synonym of manni: Wesson, L.G. 1939: 180; of floridanus (and its junior synonym flavus): MacKay, 1993a: 289.

Worker
Fusca, mandibulis, antennis (clava obscuriore), articulationibus pedum, tarsis et pedunculi segmenti 1. basi testaceis; nitida, metathorace opaco, pilosa, scapis pedibusque pube longa, obliqua vestitis; capite disperse punctato (punctis piligeris) praetereaque microscopice irregulariter aciculato, foveis antennalibus curvatim, genis longitrorsum rugosis, clypea media subtiliter, acute carinato, lateribus rugoso, mandibulis striatis, latiusculis, 5 dentatis; thoracis dorso profunde impresso, promesonoto convexo, nitido, disperse punctato et subtilissime aciculato, metanoto opaco, dentibus erectis armato, meso- et metapleuris longitrorsum rugosis et creberrime punctatis ,. abdominis pedunculi segment 1. antice longe petiolato, superne cum nodo transverso, medio impresso, 2. praecedente circiter dimidio latiore, transverse ovali. Long. 3-31/ 4 mm.

(Wheeler 1903) Length 2.5-3.25 mm. Mandibles rather broad, 5-toothed. Clypeus moderately convex, broadly rounded in front, with a distinct median carina. Antennae 12-jointed, scape extending beyond the posterior angle of the head a distance fully equal to twice its breadth; first funicular joint as long as the three succeeding joints together; joints 3-8 nearly as long as broad; club 3-jointed, the two basal joints subequal, together shorter than the terminal joint. Thorax long, rather robust, not much wider in front than behind, without abrupt declivity at the juncture of the neck and pronotum, pro- and mesonotum convex; mesoepinotal constriction very deep and broad. Epinotal spines small, not longer than broad at the base, directed upward. Petiole from above nearly three times as long as its greatest width which is in the middle; in profile the node is low and rounded above, the anterior slope very long, at first nearly horizontal, then gradually as.cending, the posterior slope shorter, somewhat flattened; summit of node distinctly impressed or concave when seen from behind; ventral surface of peduncle with a long but not very prominent tooth. Postpetiole fully half again as broad as the petiole, a little broader than long, nearly square, its anterior angles prominent, its dorsal surface in profile very convex, especially in front. Gaster rather large, of the usual shape. Sting well developed. Legs robust.

Mandibles longitudinally striated. Clypeus smooth, especially behind, its sides longitudinally rugose. Head smooth and shining above and behind, sparsely punctate and irregularly and delicately reticulate. Antennal foveal with curved, parallel rugal; front and cheeks with straight rugal. Neck opaque and delicately rugose; pro- and mesonotum shining, very finely and irregularly reticulate, pleural, epinotum and mesoepinota,l constriction subopaque, coarsely reticulate-rugose; in the constriction and on the meso- and metapleural the rugae have a distinctly longitudinal trend. Declivous surface of epinotum smooth and shining. Petiole and postpetiole shining and finely reticulate above, more opaque and reticulate-rugose on the sides. Gaster smooth and shining, finely and irregularly reticulate.

Hairs white, long and very abundant, obtuse but not clavate, erect on the trunk, suberect on the legs and antennal. Black or rich dark-brown, mandibles, antennal, except. the club, frontal carinal, thorax, pedicel and legs yellowish-red or testaceous. In some specimens the dorsal surface of the thorax and nodes is blackened, while in others the whole of the thorax, nodes and legs is black except the peduncle of the petiole and the tarsi and joints of the legs, which are yellow.

Queen
(Wheeler 1903) Length 3.5-4 mm. Apart from the usual sexual characters, differs from the worker in having the lower surfaces of the head, thorax, pedicel and the legs more yellowish. The smooth surfaces of the body are hardly reticulate. Mesonotum adorned with a median brown blotch on its anterior half and a large comma-shaped spot on either parapsis. Scutellum, epinotum and pleurm more or less spotted with brown, and a small black spot at the insertion of the forewing. Femora and tibim infuscated in the middle. Antennal club infuscated. Wings milky-hyaline, with colorless veins and stigma. Concavity at smnmit of petiolar node very distinct; postpetiole nearly twice as broad as long. Epinotal spines distinctly shorter than broad at their bases.

Male
(Wheeler 1903) Length 2-2.25 mm. Head a little longer than broad; cheeks very short, eyes and ocelli prominent. Mandibles overlapping, 4-toothed. Clypeus convex. Antennae 13-jointed, scape about as long as the five succeeding joints, first. funicular joint about as long as the second and third together; joints 3-8 slerider, cylindrical, subequal, twice as long as broad; club 4-jointed, the three basal joints subequal, together as long as the terminal joint. Thorax long, mesonotum rounded, projecting forward, so that the head is scarcely visible when the insect is viewed from above. Epinotum with a pair of slight projections in the place of the spines. Petiole long and slender, like that of the worker but with lower node. Postpetiole as long as broad, squar.e from above, in profile with the node highest in the middle of the segment and rounded. Gaster and legs of the usual conformation.

Mandibles and clypeus subopaque, the latter coarsely rugose. Head shining, very irregularly and sparsely reticulate, in.front of the ocelli with a few shallow foveolae. Pronotum subopaque, reticulate; mesonotum very smooth and shining, finely reticulate. Scutellum and epinotum more opaque, disk of former coarsely reticulate, sides of both longitudinally rugulose. Petiole and postpetiole opaque, more shining above, delicately corrugated. Gaster very smooth and shining.

Hairs white, rather sparse and long, even on the legs and antennal scape, where they are reclinate but not appressed.

Black. Mandibles, antennae and legs white except the following portions, which are infuscated or blackened: Edges and teeth of mandibles, terminal joint of antennae, basal two-thirds of coxae, middle of femora and tibiae and last tarsal joint. Wings like those of the female.

Type Locality
Washington, D. C.