Myrmica sulcinodis

A wide ranging species that has been relatively well studied.

Identification
A member of the sulcinodis complex of the lobicornis species group. Radchenko and Elmes (2010) - A member of the lobicornis species group. It is a very distinct, obvious and attractive species as the synonymous names perelegens and eximia suggest; usually it is a rather large species (for Europe) that often appears “glossy”, being distinctly bicoloured with a dark head, gaster, tibiae and tarsi, and a dark brick-red thorax, waist and usually femurs. More formally, M. sulcinodis is characterised by its coarse regular longitudinal rugosity on the alitrunk and waist, short petiole without peduncle and with a steep and straight anterior face, and by the shape of its scape that is strongly, but usually gradually curved at the base (at most being slightly angulate) but without vertical dent or lobe (at most with a slight longitudinal ridge on its foot). M. sulcinodis most resembles Myrmica ademonia, but differs from the latter by having shorter propodeal spines and coarser rugosity on the petiole and postpetiole.

Collingwood (1979) - Deep reddish with head and gaster darker. Strongly longitudinally rugulose; frontal triangle longitudinally striate. Antennal scapes sharply but evenly curved near base. Petiole high with long anterior face and rounded steeply sloped dorsal area, never truncate. Propodeal spines stout and blunt, curved so that they lie subparallel from above, not divergent. Mesopropodeal furrow shallow. Head Index: 84.7; Frons Index: 42.8; Frontal Laminae Index: 91.4. Length: 4.0-6.0 mm.

Distribution
Boreal species, distributed from the Atlantic to the Pacific Ocean; to the north reaches forest-tundra zone, to the south on plains goes to the southern limit of the taiga zone, in the more southern regions lives only in mountains; absent from Japan. (Radchenko and Elmes 2010)

Portugal to East Siberia, Appenines to Arctic Scandinavia (Collingwood 1979).

Distribution based on Regional Taxon Lists
Palaearctic Region: Albania, Andorra, Armenia, Austria, Belgium, Bulgaria, China, Croatia, Czech Republic, Democratic Peoples Republic of Korea, Denmark, Estonia, Finland, Georgia, Germany, Greece, Iberian Peninsula, Latvia, Mongolia, Montenegro, Netherlands, Poland, Republic of Korea, Romania, Russian Federation, Slovakia, Slovenia, Spain, Sweden, Switzerland, United Kingdom of Great Britain and Northern Ireland.

Biology
Radchenko and Elmes (2010) - M. sulcinodis has been comparatively well studied. In general it favours habitats that have a coarse sandy subsoil that holds a certain amount of moisture and does not completely dry out in dry periods. In northern habitats it is especially common on areas of moorlands and heathlands having the correct soil type, and is also common in open coniferous forests providing the soil is suitable. In the far north it sometimes nests under wood but in southern moorlands it normally builds its nest directly into the soil with few aboveground signs except in early spring when colonies may make small solaria. It is very common in certain sites in alpine meadows on southern mountains where it nests under stones. Many populations are highly polygynous and several queens can often be seen when a stone is turned over. Sexuals are produced in early summer and nuptial flights occur in August and September. Few flights have been observed and we suspect that generally these ants do not fly far but join small very local swarms.

In one of the first detailed population studies of this species Elmes (1974c) showed that nests of a large population living in moorland in Scotland, averaged 440 workers (mean of 40 nests) and the nests were effectively monogynous with half having no queen. Males were produced by about half the nests (average of 28 per nest) and gynes were produced by the 20% largest nests (average 65 per nest) giving an overall population sex-ratio of about 1:1. In a later study of populations on heathlands in southern England, Elmes (1987a, b) showed that M. sulcinodis are not always monogynous but can be highly polygynous with the number of queens varying from year to year. This data collected in peculiar ecological circumstances following a severe fire, showed that queen numbers cycled over a 5 year period in a regular fashion and that the cycle persisted for many years (Elmes and Keller 1993). In these populations nests were smaller averaging 163 workers and 3.7 queens per colony, weather seemed to play a part in year to year variation in worker numbers but not in queen numbers. The suggestion was that almost all the new queens are produced by a small number of large nests but almost all are randomly recruited back into all the nests of the population. Many more colonies reared males so that the sex-ratio in these populations were heavily male biased. These populations produced a great many gynandromorph mosaics with different proportions of the body being male. The only other species where we have found such a high proportion of such intercastes is Myrmica gallienii (see ecological notes for that species).

These studies were taken up and extended to a similar population living on heathland in Denmark, by Prof. J. J. Boomsma and co-workers using molecular genetical techniques (Boomsma 1993; Pedersen and Boomsma 1998, 1999a, b). Seppa et al. (1995) studied facultative polygyny in relation to habitat succession.

In the laboratory there have been a few studies of the glandular secretions of M. sulcinodis (e.g. Attygalle et al. 1983; Cammaerts et al. 1983) and cuticular hydrocarbons (Elmes et al. 2002). The chromosome number of M. sulcinodis is 56, somewhat more than most other Myrmica species (Hauschteck 1965). Both workers and queens were shown to lay trophic eggs (Wardlaw and Elmes 1995,1998) and queens can suppress the development of sexual larvae in the same way as Myrmica rubra (Elmes and Wardlaw 1983b).

Collingwood (1979) - This is a characteristic species of relatively well drained heather moorland. It is easily recognised by its generally dark colour with deep red sometimes infuscated alitrunk and legs and its strong sculpture. In Scandinavia it can only be confused with the very local lighter coloured Myrmica gallienii with its much deeper mesopropodeal furrow and clearly truncate petiole or with dark forms of Myrmica ruginodis which commonly occur on high moorland but always have the frontal triangle smooth and shining and the propodeal spines sharper and more divergent from above. M. sulcinodis nests in small colonies of up to 500 workers with single queens in dry peat or sand among heather or under flat stones, in wetter areas occasionally building small mounds of vegetable fragments for brood incubation. This is a strong robust species living by predation and scavenging. The alatae fly in August mating in the air over high ground.

Nomenclature

 *  sulcinodis. Myrmica sulcinodis Nylander, 1846a: 934 (w.q.) FINLAND. Mayr, 1855: 409 (m.); Hauschteck, 1965: 323 (k.); Donisthorpe, 1919: 1 (ergatandromorph); Santschi, 1931b: 351 (ergatandromorph). Subspecies of rubra: Forel, 1874: 76; Emery & Forel, 1879: 460; Wheeler, W.M. 1908g: 406. Status as species: Saunders, E. 1880: 215; André, 1883a: 317; Bondroit, 1912: 351; Emery, 1908a: 173; Forel, 1915d: 29; Donisthorpe, 1915d: 122; Emery, 1916b: 119; Finzi, 1926: 86; Bernard, 1967: 121; Kutter, 1977c: 70; Arnol'di & Dlussky, 1978: 531; Collingwood, 1979: 57; Seifert, 1988b: 7; Atanassov & Dlussky, 1992: 87. Senior synonym of derzhavini: Kupyanskaya, 1986b: 94; of myrmecophila: Boven, 1970a: 130; Seifert, 1988b: 8; of nigripes: Seifert, 1988b: 7; of perelegans: Mayr, 1855: 408; Smith, F. 1855b: 120; of sulcinodoruginodis, sulcinodoscabrinodis Forel: Bernard, 1967: 121; of eximia: Radchenko, 1994g: 81; of sulcinodoscabrinodis Ruzsky, vicaria: Radchenko & Elmes, 2010: 294. See also: Radchenko, 2007: 28; Radchenko & Elmes, 2010: 293.
 * perelegans. Myrmica perelegans Curtis, 1854: 214, pl. 23, figs. 15-17 (w.q.m.) GREAT BRITAIN. Junior synonym of sulcinodis: Mayr, 1855: 408; Smith, F. 1855b: 120.
 * nigripes. Myrmica sulcinodis var. nigripes Ruzsky, 1895: 32 (w.q.m.) RUSSIA. [Also described as new by Ruzsky, 1896: 73.] Subspecies of sulcinodis: Ruzsky, 1936: 95; Weber, 1948a: 268; Sadil, 1952: 244. Junior synonym of sulcinodis: Seifert, 1988b: 7.
 * sulcinodoscabrinodis. Myrmica sulcinodoscabrinodis Ruzsky, 1895: 32 (w.q.m.) RUSSIA. [Also described as new by Ruzsky, 1896: 73.] Junior syonym of sulcinodis: Radchenko & Elmes, 2010: 294.
 * myrmecophila. Myrmica myrmecophila Wasmann, 1910: 516 (q., actually Mermis-infested w.) AUSTRIA. Junior synonym of sulcinodis: Boven, 1970a: 130; Seifert, 1988b: 8; Radchenko & Elmes, 2003a: 239.
 * sulcinodoruginodis. Myrmica ruginodis var. sulcinodoruginodis Donisthorpe, 1915d: 121 (w.) GREAT BRITAIN. [Myrmica rubra var. sulcinodoruginodis Emery & Forel, 1879: 461. Nomen nudum, attributed to Forel.] Junior synonym of sulcinodis: Bernard, 1967: 121.
 * sulcinodoscabrinodis. Myrmica sulcinodis var. sulcinodoscabrinodis Forel, 1915d: 29 (diagnosis in key) (w.) SWITZERLAND. [Myrmica rubra var. sulcinodoscabrinodis Forel, 1874: 77. Nomen nudum. Unresolved junior primary homonym of sulcinodoscarbinodis Ruzsky, above.] Junior synonym of sulcinodis: Bernard, 1967: 121.
 * derzhavini. Myrmica sulcinodis subsp. derzhavini Ruzsky, 1920: 76 (w.) RUSSIA. Junior synonym of sulcinodis: Kupyanskaya, 1986b: 94.
 * vicaria. Myrmica sulcinodis subsp. vicaria Kuznetsov-Ugamsky, 1928b: 33 (w.) RUSSIA. Junior synonym of sulcinodis: Radchenko & Elmes, 2010: 294.
 * eximia. Myrmica sulcinodis subsp. eximia Kupyanskaya, 1990: 104, figs. 17, 18 (w.q.m.) RUSSIA. Junior synonym of sulcinodis: Radchenko, 1994g: 81.

Etymology
Radchenko and Elmes (2010) - from a combination of the Latin words sulcus = ridge or furrow, and nodus = knot or lump, to describe the "deeply wrinkled" sculpture of the petiole and postpetiole.