Temnothorax punctithorax

Known only from three type specimens.

Identification
Mackay (2000) - A member of the Temnothorax tricarinatus species complex. This species is easily recognized as the mesosoma (side of pronotum with striae mixed with punctae) is completely punctate with large punctures, which are nearly foveolate. The head is predominantly smooth and shining. The antenna has 12 segments and the medial clypeal carina is moderatelywell developed. The propodeal spines are small, but acute, and the node of the petiole is blunt.

The nearly foveolate punctures on the dorsum of the mesosoma would separate this species from nearly all others in North America. This species differs from Temnothorax mexicanus as the dorsum of the postpetiole is punctate (smooth and shining in Temnothorax mexicanus) and from Temnothorax cokendolpheri in that the postpetiole is not noticeably broadened and it is dark brown in color (Temnothorax cokendolpheri is pale yellow). The propodeal spines are also developed and acute, whereas the armature of Temnothorax cokendolpheri are simple, blunt angles. The distributions (central Mexico vs. New Mexico and Texas for Temnothorax cokendolpheri) will help in the confirmation of the identification. This species can be distinguished from Temnothorax manni and Temnothorax bristoli by the presence of a moderately well developed medial clypeal carina (absent or not more developed than the surrounding carinae in Temnothorax manni and Temnothorax bristoli). Additionally the side of the pronotum is covered with punctae and striae in Temnothorax punctithorax; the sides of the pronoti of Temnothorax manni and Temnothorax bristoli are predominantly smooth and shining, with fine striae.

Distribution
Mexico: Toluca.

Distribution based on Regional Taxon Lists
Neotropical Region: Mexico.

Abundance
Only known from types.

Nomenclature

 *  punctithorax. Leptothorax (Myrafant) punctithorax Mackay, W.P., 2000: 392, figs. 31, 151, 152 (w.) MEXICO. Combination in Temnothorax: Bolton, 2003: 272.

Worker
Mandibles with 5 teeth, only 2 or 3 well defined; anterior border of clypeus straight, clypeus concave, but with well formed medial carina and a few carinae near lateral edges, remainder of clypeus polished and shining; vertex slightly concave; none of the sutures break sculpture of mesosoma; propodeal spines short (> 0.04mm), but toothlike; petiole with well developed, subpeduncular flange, anterior petiolar face concave, posterior face convex, petiolar node rounded and blunt as seen in profile.

Hairs erect on most surfaces, except antennal scape and legs, where they are suberect or decumbent.

Sculpture characteristic of this species, consisting of costulae mixed with punctures on head, with strongly shining background, entire mesosoma densely covered with large punctures, nearly the size of foveolate punctures, especially on top of mesosoma, bottoms strongly shining, making them reflect like jewels, petiole and post-petiole strongly and densely punctate, gaster smooth and shining.

Color: medium brown. Worker measurement (mm): HL 0.62-0.70, HW 0.52-0.54, SL 0.49-0.54, EL 0.14-0.17, WL 0.65-0.77, PW 0.13-0.18, PL 0.20-0.23, PPW 0.23-0.25, PPL 0.16-0.17. Indices: CI 77-84, SI 77-79, PI 65-78, PPI 144-147.

Type Material
MEXICO, 19 mi. E. Toluca, 9600', 6-viii-1961, L. B. Carney #41. Holotype worker and 2 paratype workers.

Etymology
Morphological, for the heavily punctate mesosoma of the worker.

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).
 * Mackay W. P. 2000. A review of the New World ants of the subgenus Myrafant, (genus Leptothorax) (Hymenoptera: Formicidae). Sociobiology 36: 265-444.
 * Vásquez-Bolaños M. 2011. Lista de especies de hormigas (Hymenoptera: Formicidae) para México. Dugesiana 18: 95-133