Temnothorax morongo

All known collections of this species are from pitfall traps, suggesting that this is a ground-nesting ant.

Identification
Snelling et al. (2014) - First gastral tergum of worker slightly shiny and finely reticulate, with sparse blunt stiff erect setae; mesosoma dull and contiguously punctate between widely spaced longitudinal rugae and pronotal dorsum with transverse anterior carina; propodeal spines long; postpetiole in dorsal view wide.

In the keys of Creighton (1950) and Mackay (2000) T. morongo will run to Temnothorax silvestrii, an arboreal species from Arizona, which it resembles. In T. silvestrii the sculpture of the head and mesosoma is coarser, the head is proportionately a little broader, the propodeal spines are much shorter and the metafemora are much more robust, about three times longer than thick in dorsal view (also see Creighton 1953).

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

Castes
Known only from the worker caste.

Nomenclature

 *  morongo. Temnothorax morongo Snelling, Borowiec & Prebus, 2014: 50, figs. 9, 19, 24–26 (w.) MEXICO.

Worker
measurements (mm) (6 measured): EL 0.152–0.218 (0.173); HFL 0.545–0.763 (0.652); HFW 0.116–0.151 (0.139); HL 0.659–0.87 (0.761); HW 0.537–0.718 (0.607); IOD 0.447–0.611 (0.506); OMD 0.182–0.237 (0.209); PPW 0.270–0.348 (0.302); PSL 0.155–0.227 (0.194); PTW 0.171–0.213 (0.191); PW 0.381–0.510 (0.433); SL 0.544–0.749 (0.627); WL 0.816–1.050 (0.931). Indices: CI 77.3–82.5 (79.8); FI 102–112 (107); OI 21.1–25.1 (22.7); PI 150–165 (158); PSI 22.2–28.3 (25.4); SI 79.5–86.1 (82.4).

Head longer than broad in frontal view; posterior margin transverse and lateral margins essentially parallel. Antenna 12-segmented; scape slightly exceeding posterior margin; apical club distinctly 3-segmented. Eye small, IOD 2.80–3.13 × EL; EL about 0.75–0.92 × OMD. Mandibles coarsely longitudinally rugose. Head opaque and finely reticulate between fine longitudinal rugae; interrugal spaces of clypeus shiny and weakly sculptured. Sparse yellowish very short and stout erect setae on front of head; hypostomal area with scattered very short fine setae.

Mesosoma slender, WL 2.06–2.24 × PW; mesosomal dorsum essentially flat in profile. Propodeal spines well developed, distinctly longer than distance between their bases; in profile directed distad or slightly down–curved; in dorsal view slightly in-curved. Entire mesosoma opaque or nearly so between slightly irregular longitudinal rugae; anterior margin of pronotal disc with sharp transverse carina. Dorsum with sparse yellowish short, flattened setae. Metafemur slender, 3.98–5.32 times longer than wide in dorsal view.

Petiole node robust and cuboid in profile; acute subpetiolar tooth present. Postpetiole node rounded in profile; in dorsal view much broader than petiole node. Sculpture and pilosity of both nodes similar to those of mesosomal dorsum.

Gaster in dorsal view 2.01–2.29 times wider than postpetiole; slightly shiny and first tergum wholly finely reticulate and with sparse yellowish, slender suberect to erect setae.

Color of body yellowish to light orange, gaster and appendages slightly lighter.

Type Material
Holotype worker, MEXICO: BAJA CALIFORNIA: 19 km WNW Bahia de los Angeles, 28.98° -113.75°, 1.vi.1997 (A. Suarez & T. J. Case), Sonoran desert, in pitfall trap (CASENT0339305). Paratypes. Same data as holotype, 1 worker (CASENT0339305) UCDC.

Etymology
Named for the Morongo, a band of the Cahuilla people who occupied occupied the northern part of this species range, in what is now Joshua Tree National Park. The name is a noun in apposition.

References based on Global Ant Biodiversity Informatics

 * Snelling R.R., M. L. Borowiec, and M. M. Prebus. 2014. Studies on California ants: a review of the genus Temnothorax (Hymenoptera, Formicidae). ZooKeys 372: 2789. doi: 10.3897/zookeys.372.6039