Myrmica lonae

Similar to Myrmica sabuleti but much less thermophilous and inhabiting more shady, relatively cooler and humid microhabitats.

Identification
Radchenko and Elmes (2010) – A member of the sabuleti complex of the scabrinodis species group (see also Radchenko and Elmes 2004). It is very similar to Myrmica sabuleti and differs from it mainly by the extremely well-developed, large lobe at the base of scape, which is raised above the level of the dorsal plane of scape, and by a somewhat narrower frons. However, the males of these two species are practically indistinguishable.

Key to Myrmica of Romania

Key to Myrmica of West Europe and North Africa

Distribution
Radchenko and Elmes (2010) - Central and North Europe, Balkans (from NW Italy to Bulgaria), East Europe, Asia Minor, Caucasus, West Siberia, northern Kazakhstan, Altai Mts.; all previous records of M. sabuleti east of Ural Mts. belong to M. Zonae (see Radchenko 1994d).

Distribution based on Regional Taxon Lists
Palaearctic Region: Austria, Belgium, Bulgaria, Croatia, Czech Republic, Finland, Germany, Greece, Hungary, Netherlands, Poland, Romania, Russian Federation, Slovakia, Slovenia, United Kingdom of Great Britain and Northern Ireland.

Biology
Radchenko and Elmes (2010) - Generally, M. lonae is a much less thermophilous species than Myrmica sabuleti and inhabits more shady, relatively cooler and humid microhabitats. For example, we found a population living on “humid heath” in the east of The Netherlands (Elmes et al. 1994) where M. lonae comprised about 15% of the population of Myrmica nests (M. ruginodis comprised about 50% and M. scabrinodis 35%). The vegetation was typical for humid heath and very little difference could be detected in the microhabitats used by these three species. M. sabuleti very rarely co-exists with Myrmica ruginodis in west Europe so the population of M. lonae was recognised as being unusual even before noting their huge scape lobes; M. sabuleti were not present on the site but nests could be found in warmer, drier areas of grassland in the same locality. On the other hand, M. sabuleti quite often coexists with M. scabrinodis on grassland sites (see notes to ecology of M. sabuleti). Four nests were excavated and ranged in population from 1 queen with 19 workers to 2 queens with almost 1600 workers.

In Finland, M. lonae is common in open pine and mixed forests where it builds nests in the moss and underlying soil. A common feature of these sites is that they are rather cold and wet in early summer but become quite hot and dry in mid and late summer. In more southerly mountains (e.g. Transcarpathia, Ukraine) we have observed M. lonae living in meadows at the forest edge and in higher mountain meadows up to 1200 m a.s.l. In these habitats nests are built in soil, often under stones, but also in decayed wood. M. sabuleti live sympatrically at these sites and appear to prefer the more open better grazed vegetation, but we have not made a detailed study of this. Nuptial flight occurs in August-September and swarms often contain both M. lonae and M. sabuleti gynes.

We indicated that M. lonae might be a morph produced in response to ecological conditions. Our evidence for this comes from unpublished observations on a site managed to produce a large population of M. sabuleti as a management strategy for the conservation of a Large Blue Buttert1y in the UK (see Thomas et al. 1998). Before management of this site in southwest England, the M. sabuleti population lived at the hotter end of a natural temperature gradient created on a south-facing slope. A few Myrmica schencki colonies lived in the hottest places while M. scabrinodis dominated the central open grassy parts, and M. ruginodis were found in the coolest conditions among gorse scrub (Ulex spp.) at the bottom of the slope. Management consisted of a mixture of burning and grazing to generally increase soil temperatures throughout the site and specifically to maximise the hot shortsward conditions favoured by M. sabuleti. After some years the distribution of Myrmica species reflected the desired outcome with M. sabuleti dominating the grassy middle part of the site, M. scabrinodis lived in the cooler conditions lower on the slope (of course there was an area of overlap between these two species) and the M. ruginodis population had decreased and nests were more or less restricted to the edges of the remaining clumps of gorse at the bottom of the slope. However, in the long grass in the glades between the gorse M. sabuleti were apparently living, in considerably more shaded cooler conditions than M. scabrinodis. These ants were generally somewhat larger, darker with a somewhat differing foraging behaviour than the M. sabuleti. By ecological differences, we would call these ants M. lonae but we were unable to make any separation from M. sabuleti using the character proposed by Seifert (see notes above) however, the scape lobes were much larger than in the typical M. sabuleti found on the site. We suggest that M. sabuleti might produce a female morph to exploit habitat that is quite cool and moist in spring but becomes quite hot and dry in summer. Based on other studies one would expect such a morph to be “physiologically more active” and this might in some way be linked to a more developed scape lobe. It would not be unusual if such characters were only expressed in the female caste and males from either lineage might mate freely with any type of female. However, this hypothesis would need testing by a series of careful breeding tests combined with physiological and molecular genetical studies.

Nomenclature

 *  lonae. Myrmica scabrinodis subsp. lonae Finzi, 1926: 103, fig. 11 (w.q.m.) FINLAND. Subspecies of sabuleti: Santschi, 1931b: 346; Stitz, 1939: 96. Junior synonym of scabrinodolobicornis: Sadil, 1952: 249; of sabuleti: Bernard, 1967: 117; Seifert, 1988b: 31. Revived from synonymy: Seifert, 1994: 12; Seifert, 1996b: 146 (in key); Radchenko, Czechowski & Czechowska, 1997: 490; Seifert, 2000c: 198. See also: Radchenko & Elmes, 2010: 194.

Etymology
Radchenko and Elmes (2010) - named for Carlo Lona (1885-1971) of Trieste, a coleopterologist and schoolteacher who participated in the 1923 Ravasini-Lona expedition to Albania; they made their ant collection available to Finzi.