Myrmica longisculpta

A high altitude species of the Himalayas.

Identification
Bharti & Sharma (2011) - Myrmica longisculpta most resembles species that Radchenko & Elmes (2010) placed in the Myrmica rugosa complex of the M. rugosa species group, which have frontal carinae merging with rugae that extend to occipital margin of head. The coarse body sculpture with the presence of very pronounced/elevated longitudinal rugae on the alitrunk clearly separates it from allied species (including Myrmica afghanica, which is not assigned to any species-group). It most resembles Myrmica rugosa but has a relatively wider frontal lobe and a petiole with longitudinal rugae than that species. The fact that some specimens in part appear to have frontal carinae that merge with rugae that surround antennal sockets is problematic. This is a very distinctive species group character which discriminates the smythiesii-group from allied groups. However Myrmica longisculpta is most unlikely to be in the smythiesii species group, species of which are generally small with weak sculpture. Moreover the exact placement of this species in a particular group will become clearer when males are found.

Distribution
Jammu and Kashmir, India.

Distribution based on Regional Taxon Lists
Oriental Region: India.

Biology
Bharti & Sharma (2011) - The species has been hand-collected from two localities (Sarthal, 32.812947°N, 75.762503°E, 2200 m a.s.l and Shopian, 33.668354°N, 74.779472°E, 3100 m a.s.l.) and from leaf litter using Winkler’s extractor at another locality (Machedi, 32.72364°N, 75.669464°E, 2000 m a.s.l.). The collection site at Machedi has a patchy Cedrus forest along with agricultural land surrounding the site; moreover the area has a lot of anthropogenic activities with dry type of environment (mean temperature during collection period 32°C, relative humidity 36.62 % and thickness of leaf litter 2.1 cm). The collection site at Sarthal has dense Cedrus forest with abundant leaf litter and no agricultural land. It remains snow clad from November to the beginning of March and has very limited anthropogenic activities with only nomads visiting the area (mean temperature during collection period 22°C, relative humidity 66.38 %, thickness of leaf litter 3.9 cm) with a comparatively wet environment. At the third collection site (Shopian) specimens were collected under a stone. The area has scattered Cedrus trees, as the forest has largely been cleared by human activities (mean temperature during collection period was 22°C and relative humidity 54 %).

The ecology of the Himalaya is temperature-dependent. The snow line occurs at an average of 6000 meters above sea level and the average altitude at which the forest disappears is 3000 meters. Two of the habitats (Machedi and Sarthal) represent the transitional zone between subtemperate and temperate Himalaya whereas the more northerly and higher Shopian site penetrates into the Palaearctic zone whose boundary in Southern Asia is largely altitudinal (where an altitude of 2000–2500 meters above sea level forms the boundary between Palaearctic and Indo-Malayan ecozones). At this altitude the microclimate plays an important role for ants like Myrmica which prefer to live under stones or in rare cases in leaf litter, because the soil temperature is comparatively higher than ambient temperature in these microhabitats (BHARTI 2008b).

Castes
Known only from the worker caste.

Nomenclature

 *  longisculpta. Myrmica longisculpta Bharti & Sharma, 2011c: 725, figs. 1-3 (w.) INDIA.

Worker
Head much longer than broad, sides parallel, occipital margin straight; mandibles with 8 teeth (apical and preapical are the largest); clypeus convex, anterior clypeal margin prominent and somewhat pointed medially and extending over mandibles, posterior margin clear, broad, extending between antennal bases; frontal carinae short, slightly broader anteriorly than posteriorly and curving outwards to merge with rugae that surround the antennal socket (in three paratype workers frontal carina of one side merges with rugae that surround antennal insertions); antennae 12 segmented; scape slender, narrow, weakly curved at base without any trace of lobe or carina, widening towards apex, just extending beyond the upper margin of head, antennae with oblique short hairs having pubescence on apical 3 segments; eyes large, placed almost at midline of head; head covered with numerous interspersed short and long suberect hairs; mandibles and clypeus also equipped with long suberect hairs.

Alitrunk dorsum feebly convex; promesonotal suture indistinct; metanotal groove broad, shallow; propodeal lobes rounded apically; propodeal spines long, sharp, projected backward, divergent; tibiae of hind and middle legs with well developed pectinate spur; petiole longer than broad, with very short anterior peduncle with a tooth like subpetiolar process, post-petiole a little longer than broad; promesonotum with long erect, as well as short hairs; propodeum with 1 to 2 pairs of short suberect hairs; petiole and post-petiole equipped with long and short suberect hairs directed backwards.

Gaster with numerous long erect to suberect hairs, and with few short suberect hairs between them.

Punctuation. Head longitudinally rugulose with punctures; clypeus convex, longitudinally rugulose, space between rugae smooth and shiny; frontal triangle highly polished and shiny; all antennal segments densely punctuated except scape, first 2 segments are minutely punctated; cephalic dorsum longitudinally rugose up to vertex behind which it is reticulated; whole of the alitrunk distinctively longitudinally coarsely rugose with much pronounced rugae; the pronotum dorsum with somewhat broken longitudinal sculpture; the lateral parts of the body with distinct longitudinal rugae, as does the petiole and postpetiole dorsum; gaster smooth, highly polished and shiny.

Type Material
Holotype: Worker, INDIA: Jammu and Kashmir: Sarthal, 32.812947°N, 75.762503°E, 2200m a.s.l., 15.vi. 2009 (coll. Sharma, Punjabi University). Paratypes: 4 workers, with same data as of holotype, not from same nest; 1 worker, INDIA: Jammu and Kashmir: Machedi, 32.72364°N, 75.669464°E, 2000 m a.s.l., 3.viii.2008 (coll. Sharma) and 1 worker, INDIA: Jammu and Kashmir: Shopian, 33.668354°N, 74.779472°E, 3100 m a.s.l., 12.ix.2009 (coll. Sharma). One paratype will be deposited in Natural History Museum, London.

Etymology
Named in reference to the presence of deep longitudinal sculpture on the alitrunk.