Temnothorax aztecus

Wheeler (1931) reports this species has been observed nesting in hollow twigs.

Identification
This species somewhat resembles M. affinis of Cuba, but is smaller, with shorter epinotal spines, differently shaped petiole and postpetiole, different coloration, etc. (Wheeler 1931)

Distribution based on Regional Taxon Lists
Neotropical Region: Cuba, Guatemala, Mexico.

Nomenclature

 *  aztecus. Macromischa azteca Wheeler, W.M. 1931b: 8 (w.q.m.) MEXICO. Combination in Leptothorax: Baroni Urbani, 1978b: 425; in Temnothorax: Bolton, 2003: 271. Senior synonym of maya: Baroni Urbani, 1978b: 425.
 * maya. Macromischa azteca var. maya Wheeler, W.M. 1937b: 458 (w.q.) GUATEMALA. Junior synonym of aztecus: Baroni Urbani, 1978b: 425.

Worker
Length 2.6-3 mm.

Head subrectangular, very nearly as broad as long, with subparallel sides, broadly rounded posterior corners and feebly convex posterior border. Eyes rather convex, at the middle of the sides. Mandibles large, 5-toothed, with convex external borders. Clypeus convex in the middle, depressed at the sides, with broadly rounded, entire anterior border. Frontal area indistinct. Antennal scapes surpassing the posterior border of the head by nearly three times their greatest diameter; first funicular joint nearly as long as the four succeeding joints together, joint 2 distinctly longer than broad, 3-8 subequal, as broad as long; club long, 3-jointed, the two basal joints fully 1 1/2 times as long as broad, together equal to the somewhat thicker apical joint. Thorax rather long, broader through the pronotum; the meso- and epinotum parallel-sided; in profile the dorsal outline is straight except for a faint but distinct transverse impression between the meso- and epinotum. Base of epinotum longer than the abrupt, concave declivity; spines as long as the declivity, directed backward and outward and slightly deflected. Petiolar peduncle as long as the node, armed anteroventrally with a slender, downwardly directed spine; node rising rather abruptly from the peduncle, broader than long, anteroposteriorly ompressed, with straight, blunt, transverse superior border, the sides straight and converging below. Postpetiole strongly convex anteriorly, from above small, nearly square, slightly narrower anteriorly and distinctly narrower than the superior border of the petiolar node. Gaster of the usual shape; sting long. Legs rather long, tibiae and median portions of the femora distinctly swollen.

Mandibles shining, striate. Head and thorax almost opaque, finely punctate, the head and clypeus also longitudinally rugulose. Thorax above irregularly rugulose, the sides of the pronotum more longitudinally, the epinotal declivity transversely rugulose. Nodes of petiole and postpetiole smooth and shining, their sides and the peduncle of the former punctate and more opaque. Gaster smooth and shining. Antennal scapes subopaque, densely punctate; legs more shining and more densely punctate. Hairs white, bristly, pointed, of uneven length, erect on the body and somewhat sparser than on the appendages, where they are more oblique.

Yellowish ferruginous; mandibles, clypeus, cheeks, gaster and legs somewhat paler and more yellow; teeth and borders of mandibles, antennal clubs, knees, posterior tibiae and posterior borders of gastric segments brown.

Queen
Length 4 mm.

Resembling the worker except in the shape and sculpture of the thorax. Mesonotum large, flattened above, as broad as long; epinotal spines stout, shorter than their distance apart at the base. Pronotum transversely, mesonotum and scutellum longitudinally, and epinotum irregularly rugulose. Color like that of the worker but with the wing insertions, epinotal spines, petiolar and postpetiolar nodes, femora and tibiae of the middle and hind legs, a broad band at the posterior end of each gastric segment and along the sides of the first, dark brown or blackish. Petiolar peduncle pale yellow; mandibular teeth black. Pilosity on the body more uniform and somewhat more abundant than in the worker.

Male
Length 2.3-2.5 mm.

Head as broad as long, prolonged and rounded behind the large, prominent eyes, without posterior corners, cheeks very short. Ocelli large, prominent. Mandibles well developed, 4-toothed, with convex external borders. Clypeus very convex in the middle, with straight, transverse anterior border. Antenna! scapes short, only four times as long as broad; funiculi long, first joint elongate, swollen; joints 2-7 more slender, subequal, about It times as long as broad; club 4-jointed, the three basal joints subequal, twice as long as broad, the terminal joint as long as the two preceding together. Mesonotum and scutellum shaped much as in the female, the former with distinct but shallow notauli (Mayrian furrows), the epinotum small, unarmed, rectangular in profile, with subequal base and declivity, the former distinctly concave anteriorly. Petiole with thick peduncle, the node in profile low, rising very gradually from the peduncle and only half as long as the segment, seen from above narrow, with straight, transverse superior border. Postpetiole rectangular as in the worker but broader than the petiolar node. Gaster like that of the worker, genitalia prominent wings rather short.

Mandibles shining, finely and indistinctly punctate; head opaque, densely and more coarsely punctate; clypeus and sides of front also longitudinally rugulose. Thorax punctate like the head but less densely, so that the surface is more shining, especially on the sides. Remainder of the body smooth and shining, with fine, sparse, piligerous punctures.

Pilosity pale, much finer, shorter and sparser than in the worker and female, and more nearly appressed on the appendages.

Black; mandibles yellowish, with brown teeth; clypeus dark brown; antennae, legs and genitalia pale brown, tarsi paler. Wings whitish hyaline, with very pale brownish veins and stigma.

Type Material
Described from a number of workers and males and a single female found by Dr. Elisabeth Skwarra nesting in hollow twigs at Mirador, Mexico.

References based on Global Ant Biodiversity Informatics

 * Dattilo W. et al. 2019. MEXICO ANTS: incidence and abundance along the Nearctic-Neotropical interface. Ecology https://doi.org/10.1002/ecy.2944
 * Fernandes, P.R. XXXX. Los hormigas del suelo en Mexico: Diversidad, distribucion e importancia (Hymenoptera: Formicidae).
 * Goodnight, C. J., and M. L. Goodnight. 1956. Some observations in a tropical rain forest in Chiapas, Mexico. Ecology 37: 139-150.
 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Kusnezov N. 1963. Zoogeografia de las hormigas en sudamerica. Acta Zoologica Lilloana 19: 25-186
 * Longino J. T. L., and M. G. Branstetter. 2018. The truncated bell: an enigmatic but pervasive elevational diversity pattern in Middle American ants. Ecography 41: 1-12.
 * Longino J. et al. ADMAC project. Accessed on March 24th 2017 at https://sites.google.com/site/admacsite/
 * Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133