Temnothorax neomexicanus

Summarized from Mackay (2000): Nests in open, dry grassy areas, in Ponderosa Pine forests or even in desert areas under rocks or in soil. Nests are monogynous and are marked by a hole in the ground and occasionally with a light, asymmetrical scattering of fine soil. Colonies are "rather small" (Cole. 1954)."

Identification
Mackay (2000) - A member of the Temnothorax tricarinatus species complex. Workers of this species have a 12-segmented antenna. the medial clypeal carina is well developed; the lateral carinae may be somewhat weakly developed. The anterior edge of the medial clypeal lobe is usually somewhat delineated by 1 or more transverse carinae. The head is covered with fine striolae, except for a central strip, which is partially smooth and shining. The node of the petiole is rounded or weakly truncate. The postpetiole is broad as seen from above (more than 1.5times the width of the postpetiole), but much less than 1/2 the width of the gaster. The propodeal spines are short and dentiform. The side of the mesosoma, petiole and postpetiole are more or less uniformly covered with a granulate or punctulate sculpture, which is so delicate that much of these areas, especially the mesosoma, are shining under various lighting conditions. The top of the mesosoma is covered with fine rugulae, which nearly form foveolate punctures. The subpeduncular process is poorly developed. consisting of a tiny bump.

The lateral carinae of the clypeus of both Temnothorax neomexicanus and Temnothorax nevadensis are very similar, in that they curve medially at the anterior part of the medial lobe of the clypeus, and connect. They can be easily separated as the head of Temnothorax neomexicanus is at least partly smooth and shining, whereas the dorsum of the head of Temnothorax nevadensis is nearly completely sculptured. It can be separated from Temnothorax carinatus in being much darker in color (Temnothorax carinatus is pale brown or brown-orange). The propodeal spines are well developed, but short (l/3 to 1/2 length of distance between bases), whereas the propodeal armature of Temnothorax carinatus consists of poorly developed angles.

Distribution
USA: Nevada, Utah, Colorado, Arizona, New Mexico, Texas. MEXICO: Chihuahua.

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

Habitat
Open, dry grassy areas; from desert through Ponderosa Pine forests.

Abundance
Common to abundant in some areas.

Foraging/Diet
An insinuater species (Lebrun 2005)

New Mexico
Cole (1953): Collections of Temnothorax neomexicanus were taken in Cimarron Canyon, between Cimarron and Ute Park, at elevations of 6,500 and 6,700 feet. The nests were in moist soil beneath stones in open, grassy areas.

Mackay and Mackay (2002) - This species nests in the soil, or under stones, in open areas. Nests are monogynous and are marked by a hole in the ground, occasionally with a light, asymmetrical scattering of fine soil. Colonies are small.

Castes
Lebrun (2005) - Average worker dry weight: 0.11 +- 0.003 (mg)

Nomenclature

 *  neomexicanus. Leptothorax neomexicanus Wheeler, W.M. 1903c: 248, pl. 12, fig. 18 (w.) U.S.A. Combination in Temnothorax: Bolton, 2003: 271. Subspecies of tricarinatus: Creighton, 1950a: 273; Smith, M.R. 1952b: 100. Revived status as species: Mackay, 2000: 374.

Worker
Length 2.25-2.5 mm. Head longer than broad. Mandibles 5-toothed. Clypeus moderately convex, broadly rounded in front, not impressed. Antennae slender, 12-jointed; scape extending to a distance equal to its own breadth beyond the posterior angle of the head; funiculus terminating in a 3-jointed club, the two basal joints of which are subequal and together shorter than the terminal joint; first funicular joint as long as the tliree succeeding joints together; joints 2-8 of the funiculus as long as broad. Thorax not much broader in front and above than behind and below; humeral angles rounded; dorsal surface flattened, without mesoepinotal suture or constriction. Epinotal spines short, robust, blunt, not longer than broad at their bases and nearly twice as far apart at their bases as long. They are directed obliquely upward, outward and backward. Petiole hardly 1 1/2 times as long as broad; distinctly wider behind than in front, sides somewhat convex; in profile the node is nearly as high as the length of the petiole, its anterior slope steep, slightly concave; the summit somewhat truncated, passing abruptly into the angular posterior declivity; ventral surface in front with a prominent tooth, directed downward and forward. Postpetiole nearly twice as broad as the petiole; nearly as long as broad, subglobular, its anterior dorsal surface in profile abruptly convex, the posterior dorsal surface more flattened. Gaster of the usual shape with slight basal angles.

Mandibles coarsely striated and punctate. Clypeus longitudinally rugose, especially on the sides, behind without rugae, smooth and shining, somewhat foveolate-punctate. Head subopaque except along a broad median strip, extending from the frontal area to the occiput, and on the posterior angles. These regions are smooth and shining. Cheeks and sides of head rather delicately and longitudinally reticulate-rugose. On the front and vertex there are also a few rather large indentations at widely separated intervals. Thorax nearly opaque, in front delicately and evenly reticulate-rugose; on the epinotum and pleurre the rugae are coarser and have a distinctly longitudinal trend. Petiole and postpetiole nearly opaque, finely reticulate-rugose. Gaster very smooth and shining.

Hairs rather sparse, silvery-white; those on the body subclavate, shorter and more erect on the head and thorax, longer and more reclinate on the pedicel and gaster. Hairs on the legs and antennae short, non-clavate, appressed.

Black. In some specimens the pedicel and thorax are dark-brown. Scape and funiculus of antennae brown. Mandibles yellow, with black teeth. Legs yellow, middle portion of the femora and tibiae and terminal tarsal joint on each foot, black.

Type Material
Mackay (2000) - USA: New Mexico, Manzanares, [seen].

Etymology
Toponym. Referring to the New Mexico origin of the type collection.