Myrmica mixta

Described from a single queen. Nothing is known about the biology of .

Identification
Radchenko and Elmes (2010) - M. mixta has an unusual combination of morphological features that seems to be intermediate between the ritae and inezae species groups. Its fairly coarse body sculpture, very long propodeal spines and fig-shaped postpetiole might lead one to place it in the ritae-group. Yet it differs from that group by its relatively short scape, not-pointed-apically propodeal lobes, not-well-marked upper lateroventral corners of head and short and rounded petiolar node. M. mixta is most similar to the Himalayan species Myrmica rigatoi, but differs from it mainly by its wider frons, shorter scape and differently shaped propodeal spines and petiole. We provisionally place M. mixta in the inezae-group although a final decision will depend upon the discovery of its workers and males.

Distribution
Only known from the type locality in Sichuan Province of China.

Distribution based on Regional Taxon Lists
Palaearctic Region: China.

Castes
Known only from the queen caste.

Nomenclature

 *  mixta. Myrmica mixta Radchenko & Elmes, in Radchenko, Zhou, et al. 2008: 770, figs. 11-15 (q.) CHINA. See also: Radchenko & Elmes, 2010: 202.

Queen
Head distinctly longer than broad, with very weakly convex sides and occipital margin, and widely rounded occipital corners; anterior clypeal margin convex, neither prominent nor notched medially. Upper lateroventral corners of head not pointed, forming only rounded blunt angle (seen in profile). Mandibles with 7 teeth. Frontal carinae curved outwards to merge with coarse rugae, which surround antennal sockets; frons very wide, but frontal lobes distinctly extended. Scape of moderate length, somewhat shorter than head length, gradually and feebly curved at the base, without any trace of lobe or carina.

Alitrunk relatively short and high. Propodeal lobes roundcd. Propodeal spines very long, slender and acute, slightly widened at the base, directed backwards and distinctly curved down along their length. Petiole with very long peduncle (about as long as half the total petiolar length) and broadly-rounded node. Postpetiole somewhat higher than long, fig-shaped in dorsal view. Spurs of middle and hind tibiae well developed and pectinate.

Sculpture coarse. Frons with coarse longitudinal sinuous rugae, occiput and temples coarsely reticulate; clypeus longitudinally rugose, frontal triangle smooth: mandibles finely rugose. Scutum with quite coarse sinuous longitudinal rugae, pronotum and scutellum coarsely reticulate. Propodeum and mesopleura quite coarsely longitudinally rugose. Petiolar node and postpetiole rugose.

Whole surface of body between rugae at most with very fine superficial microreticulation, appears shiny. Gaster smooth and shiny.

Occipital and lateral margins of head with fairly sparse suberect hairs. Alitrunk and waist with more abundant, long erect hairs. Scape and tibiae with subdecumbent pilosity. Body colour reddish brown, appendages somewhat lighter.

Measurements (mm) and indices of the holotype queen: HL 1.22, HW 1.02. FW 0.50, FLW 0.60, SL 1.12, AL 2.04, AH 0.72, SCW 0.56, SCL 0.78, HTL 1.08, PL 0.70, PW 0.32, PH 0.41, PPL 0.50, PPW 0.50. PPH 0.51, ESL 0.56, ESD 0.62; CI 1.20, FI 0.49m FLI 1.20, SI1 0.92, SI2 1.10, PI1 1.70, PI2 0.69, PI3 0.32, PPI1 0.98, PPI2 1.02, PPI3 1.55, PPI4 0.49, ESLI 0.55, ESDI 1.10, AI 1.57, SCI 1.40.

Type Material
Holotype queen, CH [China], N Sichuan, NW Dujiang-yan, 3 km WSW Shapingguan, 31-10-50 N/103-28-01 E, H = 1490 m, 12.vii.[20]05, leg. I. Belousov & I. Kabak. (ZISP).

Etymology
From the Latin mixtus = mixed, that refers to the unusual combination of features of this species.