Myrmica liui

This species was found nesting in the soil of an alpine meadow at elevation 2573m.

Identification
Chen et al. (2016) - This species belongs to the lobicornis species group, which is one of the three most diverse species group of the Old World, containing 22 species (Radchenko and Elmes 2010). Radchenko and Elmes (2010) divided this group into five species complex, based on worker characters. This species shares features of kasczenkoi-complex of this group by mesosoma with less coarse sinuous longitudinal rugosity, propodeal spines shorter (ESLI ≤ 0.35), petiole of various shape, but never with well developed flattened dorsal plate. The kasczenkoi-complex includes 5 species: Myrmica angulinodis, Myrmica commarginata, Myrmica displicentia, Myrmica kamtschatica and Myrmica kasczenkoi. M. liui is similar to M. angulinodis, but the latter propodeal spines that curved inward when viewed from above. M. liui is very similar to M. commarginata, but differs from the latter by dorsum of petiole somewhat convex and steeply sloping backward, without dorsal plate; on the other hand, the latter possesses unique morphological feature: mesonotum and propodeum are strongly conwtricted laterally, so that dorsal surface of them is narrow and form a sharp fidges, merging with the outer bases of propodeal spines. M. liui also semblables to M. displicentia, but differs from the latter by dorsum of petiole without dorsal plate. This species is also similar to M. kasczenkoi, but differs from the latter by antennal scape with ridge at the base of the inner margin; propodeal spines thin, short, only 1/2 times longer than the distance between them, somewhat narrow at the base, backward and curved downward; petiole without dorsal plate. This species resembles to M. kamtschatica, but well differs from the latter by frontal carinae merges with the rugae that extend to the margin of the head, petiole without dorsal plate.

This species also is similar to Myrmica sulcinodis Nylander of the sulcinodis-complex, but differs from the latter by sides of petiolar node with punctures and short rugae less coarse than those on the mesosoma. Metanotal groove very weak or absent. Anterior surface of petiole concave, meeting the dorsal one through a rounded angle, dorsum of node somewhat convex and steeply sloping backward.

Distribution based on Regional Taxon Lists
Palaearctic Region: China.

Nomenclature

 *  liui. Myrmica liui Chen, Zhue & Huang, 2016: 99, figs. 14-16 (w.) CHINA.

Worker
Holotype. HL 1.13, HW 0.93, FW 0.40, FLW 0.50, SL 0.88, PW 0.65, ML 1.38, PL 0.38, PH 0.38, ESL 0.18, CI 1.21, FI 0.43, FLI 1.25, SI1 0.78, SI2 0.94, ESLI 0.19. Paratype workers (n = 6). HL 1.10−1.15, HW 0.91−0.94, FW 0.35−0.41, FLW 0.45−0.50, SL 0.85−0.90, PW 0.60−0.71, ML 1.33−1.40, PL 0.32−0.42, PH 0.33−0.41, ESL 0.13−0.17, CI 1.18−1.22, FI 0.31−0.34, FLI 1.28−1.33, SI1 0.77−0.82, SI2 0.90−0.96, ESLI 0.18−0.21.

Holotype. Head longer than broad, with weakly convex sides and posterior margin, and broadly rounded posterior corners; anterior clypeal margin broadly rounded, shallowly notched medially. Frontal carinae very feebly curved, merging with the rugae that extend to the margin of the head. Frons wide, frontal lobes much extended. Antennal scape long (SI2 0.94), slightly shorter than head width, gradually though distinctly curved at the base, with ridge on the inner margin.

Mesosoma in profile view weakly convex; promesonotal suture in dorsal view visible, metanotal groove very weak or absent. Propodeal lobes rounded. Propodeal spines short, blunt, directly backward and downward. Petiole with anterior surface concave, meeting the dorsal one to form a blunt angle, dorsum of node somewhat convex and steeply sloping backward, without dorsal plate. Postpetiole shorter than high, with convex dorsum. Spurs on middle and hind tibiae well-developed and pectinate.

Head with coarse longitudinal rugae on the whole dorsum, number of rugae between frontal carinae level with the eyes < 20. Posterior part and lateral sides of the head coarsely reticulated. Clypeus with coarse longitudinal rugae. Frontal triangle with a few longitudinal rugae, space between rugae shiny.

Dorsum and sides of mesosoma with less sinuous longitudinal rugae, space between rugae smooth and shiny. Petiole and postpetiole with short rugae, and densely punctate.

Head with abundant, long, suberect hairs at lateral margins; dorsum of mesosoma with longer hairs, petiole with 6−8 long and some shorter hairs. Antennal scape and tibiae with subdecumbent hairs. Head and gaster colored dark brown, mesosoma reddish-brown, appendages lighter.

Type Material
Holotype worker. Helanshan, Inner Mongolia Autonomous Region, China, 38°52'29"N, 105°53'42"E, 2597m. 8.vii.2010, leg. Zhilin Chen, No. G100237. Paratypes. 5 workers, data as per holotype. Deposited in the Insect Collection of.

Etymology
The specific epithet is the Chinese name Gongquan Liu, who was a famous Chinese calligrapher in the Tang Dynasty.