Temnothorax myrmiciformis

The type series specimens were all collected in pitfall traps in grassy areas in oak woodland. The species has otherwise been collected in coastal sage scrub, chaparral, and Sonoran desert. The specimen collected by Creighton was taken near the beach at Bahia San Quintín, under a clump of Mesembryanthemum.

Identification
Snelling et al. (2014) - Large, gracile species with large eyes; scape extending well beyond posterior margin; dorsum of mesosoma evenly sloping from pronotum to base of propodeal spines; side of head behind eyes with numerous standing setae along margin.

The large size, depressed mesosomal profile and long scapes will separate this from all other western Temnothorax. These features are shared with Temnothorax paiute, as is the presence of short setae on the eyes. The two differ, however, in the much more conspicuously and coarsely sculptured head and mesosoma of T. myrmiciformis.

Key to Temnothorax of California

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

Castes
Known only from the worker caste.

Nomenclature

 *  myrmiciformis. Temnothorax myrmiciformis Snelling, Borowiec & Prebus, 2014: 52, figs. 10, 19, 24–26 (w.) UNITED STATES.

Worker
measurements (mm) (9 measured): EL 0.216–0.250 (0.217); HFL 0.759–0.908 (0.789); HFW 0.150–0.187 (0.164); HL 0.774–0.904 (0.821); HW 0.624–0.748 (0.665); IOD 0.525–0.636 (0.556); OMD 0.210–0.255 (0.220); PPW 0.243–0.285 (0.265); PSL 0.164–0.210 (0.182); PTW 0.174–0.210 (0.193); PW 0.467–0.550 (0.493); SL 0.728–0.863 (0.748); WL 1.012–1.175 (1.049). Indices: CI 77.4–84.0 (81.0); FI 116–127 (118); OI 26.8–28.9 (26.3); PI 128–140 (138); PSI 19.9–23.6 (22.2); SI 89.4–97.6 (90.7).

Head longer than broad in frontal view, widest anterior to eyes; posterior to eyes evenly narrowed toward slightly convex posterior margin. Antenna 12-segmented; scape exceeding posterior margin by more than its apical width; 3-segmented apical club poorly defined. Eyes with scattered very short setae arising between ommatidia; IOD 2.34–2.60 × EL; EL 0.96–1.15 × OMD. Mandibles coarsely longitudinally rugose. Clypeus with strong median carina and without flanking carinae between it and carina defining median lobe; lateral lobes each with several short longitudinal carinae. Malar area with several irregular coarse longitudinal rugae, some of which extend back mesad of eyes to posterolateral corners; others curve mesad over antennal fossa; interspaces shiny and weakly reticulate; frons and vertex shiny between fine sparse piligerous punctures. Dorsum with numerous long standing setae, longest exceeding one-half minimum eye diameter, setae slender and not appreciably flattened; venter with several shorter setae on each side.

Mesosoma slender, WL 2.07–2.17 × PW; in profile, dorsum sloping from pronotum to base of propodeal spines; propodeal spines about as long as distance between their bases. Mesosoma moderately shiny and weakly sculptured between coarse irregular longitudinal rugae; posterior face of propodeum with weak transverse rugae. Metafemur 4.77–5.15 times longer than wide in dorsal view. Entire length of dorsum with >40 long fully erect setae similar to those of frons, longest subequal to minimum eye diameter.

Petiole with short anterior peduncle; node thick-triangular in profile, posteriorly gently curved; subpetiolar tooth short, acute. Postpetiole node high and subrectangular in profile. Postpetiole node 1.28–1.40 times as wide as petiole node. Both nodes longitudinally rugose, petiole node with weakly reticulate interspaces at side, postpetiole weakly reticulate throughout. Setae on nodes numerous and similar to those of mesosomal dorsum.

Gaster in dorsal view 3.34–4.15 times wider than node of postpetiole; disc of first tergite moderately shiny and very finely reticulate throughout, between sparse fine piligerous punctures. Segments with numerous suberect setae similar to those of mesosoma.

Dark brown, gaster darker posteriorly.

Type Material
Holotype worker, U.S.A.: CALIFORNIA: Riverside Co.: Skinner Reservoir, 1360 m, 33.59° -117.07°, 1–31.iii.1997 (T. Prentice) oak woodland, 1 worker (LACMENT299342). Paratypes. U.S.A.: CALIFORNIA: Riverside Co.: Skinner Reservoir, 1360 m, 33.59° -117.07°, 1–31.iii.1997 (T. Prentice) oak woodland, 1 worker (LACMENT299339) LACM, 1 worker (LACMENT299340) LACM; Riverside Co.: Skinner Reservoir, 1360 m, 33.59° -117.07°, 1–30.ix.1997 (T. Prentice) oak woodland, 1 worker (LACMENT299341), 1 worker (LACMENT299337).

Etymology
The name is derived from the superficial resemblance to species of the unrelated genus Myrmica.