Messor structor

Unicoloniality and lack of swarming flights reported from Retz, Austria (Schlick-Steiner et al., 2005). In Greece, Messor structor appears to be mountain species, it was collected in mountain habitats between 535 and 1340 m a.s.l., mostly pastures, often close to coniferous forests, only one locality was in shadow mountain valley, on roadsides close to deciduous forest (Salata & Borowiec, 2019).

Identification
Steiner et al. (2018) - Worker and queen. Mostly lighter than Messor ponticus and Messor muticus. Discrimination from Messor ibericus, M. ponticus, and Messor mcarthuri by long 1st funicular segment, by base of scape with rounded lobe, and by coarser sculpture of mesopleuron, from M. ponticus by abundant standing setae on side of head. Head more irregularly costate than in M. mcarthuri. Surface of 1st gastral tergite less imbricate than in M. ibericus and M. mcarthuri, similarly to M. ponticus and M. muticus.

Worker. Similarly sized as M. ibericus and M. muticus, smaller than M. ponticus and M. mcarthuri. For individuals difficult to discriminate from M. ibericus, M. ponticus, or M. muticus using qualitative morphology, linear discriminant functions based on morphometrics is available.

Queen. Larger than M. ibericus, similarly sized as the other three species. Discrimination from M. ibericus by reduced reticulation and rugosity of anepisternum and katepisternum.

Distribution based on Regional Taxon Lists
Palaearctic Region: Austria, Bulgaria, Czech Republic, France, Hungary, Romania, Slovenia.

Habitat
A range of xeric habitats and, in some areas, open well drained anthropogenic habitats (lawns, abandoned fields, etc.).

Biology
Stoyanov et al. (2015) - Messor structor are harvester ants storing seeds in underground granaries. Being major seed consumers in xeric habitats they influence the vegetation by depleting and dispersing seeds (Azcarate, Peco 2003, MacMahon et al. 2000, Schlick-Steiner et al. 2005). According to Seifert (1996), Central European populations of the harvester ant genus Messor are currently considered to constitute a single species Messor structor. It has been reported that M. structor ants live mainly in polygynous colonies and could be members of unicolonial populations (Schlick-Steiner et al. 2005). Messor structor is one of the most widespread steppe species. It is well adapted to different conditions and occurs in all of Europe. In Bulgaria this ant is found all over the country in medium-sized populations and occur in plain desolate terrains, mountainous slopes, outskirts of mixed woodland zones and in open well-drained areas such as abandoned fields, pastures, and overgrown lawns.

This study examined genetic variability among populations of Messor structor from various localities (n=36 nests) in from Southern Bulgaria using isoenzymic analysis. Three of the four enzyme loci used were found to be polymorphic. Observed and expected heterozygosities (Ho and He) ranged from 0.0 to 0.111 and from 0.168 to 0.372, respectively. Nei’s (1972) genetic distance was found to range from 0.001 (between Boliarino and Lubenova mahala) to 0.462 (between Chirpan and Merichleri). The estimated mean F-IS and F-ST values from isozyme data were 0.8738 and 0.1432, respectively. Two of the studied populations were grouped separately in dendrograms as compared to all other populations which formed a large cluster consisting of three sub-clusters.

mtDNA. Thirty-one haplotypes of COI (1375 bp) known; (GenBank).

Nomenclature

 *  structor. Formica structor Latreille, 1798: 46 (w.m.) FRANCE.
 * Latreille, 1802c: 237 (q.).
 * Combination in Manica: Jurine, 1807: 279.
 * Combination in Atta: Latreille, 1809: 130; Lepeletier de Saint-Fargeau, 1835: 174; Mayr, 1855: 464; Smith, F. 1858b: 162.
 * Combination in Myrmica: Nylander, 1856b: 85.
 * Combination in Aphaenogaster: Roger, 1863b: 29.
 * Combination in A. (Messor): Forel, 1892i: 316.
 * Combination in Stenamma (Messor): Emery, 1898c: 126.
 * Combination in Messor: Emery, 1897f: 238; Ruzsky, 1903b: 315; Emery, 1908e: 455.
 * Subspecies of barbarus: Emery, 1908e: 455; Forel, 1910a: 9; Karavaiev, 1910b: 67; Forel, 1911d: 346; Emery, 1912f: 96; Karavaiev, 1912a: 10; Stitz, 1914: 69; Emery, 1914d: 156; Emery, 1915h: 1; Wheeler, W.M. & Mann, 1916: 170; Emery, 1916b: 143; Santschi, 1917e: 91; Escherich, 1917: 327; Menozzi, 1918: 83; Santschi, 1921a: 110; Menozzi, 1921: 26; Emery, 1921b: 210; Emery, 1921f: 73; Soudek, 1922: 34; Finzi, 1923: 3; Emery, 1924b: 12; Ceballos, 1956: 301.
 * Status as species: Latreille, 1802c: 236; Latreille, 1809: 130; Lepeletier de Saint-Fargeau, 1835: 174; Schilling, 1839: 56; Brullé, 1840: 84; Schenck, 1852: 113; Mayr, 1855: 464 (redescription); Nylander, 1856b: 85; Gredler, 1858: 30; Smith, F. 1858b: 162; Roger, 1859: 253; Mayr, 1861: 66 (in key); Smith, F. 1861a: 35; Roger, 1863b: 29; Mayr, 1863: 397; Mayr, 1867a: 93 (redescription); Emery, 1869b: 17; Walker, 1871: 10; Forel, 1874: 74 (in key); André, 1874: 195 (in key); Mayr, 1877: 14; Emery, 1878b: 58; Emery & Forel, 1879: 461; Mayr, 1880: 33; Emery, 1881b: 534; André, 1883b: 353 (in key); Forel, 1886e: clxviii; Forel, 1889: 257; Nasonov, 1889: 37; Saunders, E. 1890: 204; Forel, 1892i: 316; Dalla Torre, 1893: 105; Forel, 1895d: 227; Ruzsky, 1896: 74; Emery, 1898c: 140; Ruzsky, 1902a: 235; Ruzsky, 1902d: 27; Ruzsky, 1903b: 315; Forel, 1904b: 373; Ruzsky, 1905b: 728; Forel, 1906c: 190; Forel, 1907e: 15; Forel, 1909c: 104; Forel, 1915d: 35 (in key); Bondroit, 1918: 150; Kuznetsov-Ugamsky, 1923: 256; Müller, 1923b: 60; Finzi, 1924a: 13; Lomnicki, 1925b: 2; Wheeler, W.M. 1926: 2; Donisthorpe, 1926a: 7; Menozzi, 1926b: 181; Karavaiev, 1926b: 101; Karavaiev, 1927a: 286; Kuznetsov-Ugamsky, 1927a: 92 (in key); Karavaiev, 1927c: 261 (in key); Kutter, 1927: 99; Kuznetsov-Ugamsky, 1929d: 12; Finzi, 1929: 90; Karavaiev, 1929b: 209; Finzi, 1930d: 312; Cori & Finzi, 1931: 238; Santschi, 1931a: 4; Soudek, 1931: 8; Arnol'di, 1933b: 600 (in key); Karavaiev, 1934: 108; Grandi, 1935: 100; Zimmermann, 1935: 14; Finzi, 1936: 160; Finzi, 1939c: 155; Donisthorpe, 1950e: 1059; Consani & Zangheri, 1952: 40; Bernard, 1955a: 361 (in key); Bernard, 1956b: 258; Baroni Urbani, 1964a: 2; Baroni Urbani, 1964b: 41; Baroni Urbani, 1964c: 150; Bernard, 1967: 144 (redescription); Baroni Urbani, 1968b: 436; Collingwood & Yarrow, 1969: 64; Baroni Urbani, 1971c: 66; Baroni Urbani, 1974: 232; Collingwood, 1978: 81 (in key); Schembri & Collingwood, 1981: 427; Agosti & Collingwood, 1987b: 271 (in key); Dlussky, Soyunov & Zabelin, 1990: 224; Casevitz-Weulersse, 1990b: 156 (in key); Arakelian, 1994: 38; Bolton, 1995b: 257; Mei, 1995: 762; Cagniant & Espadaler, 1998: 423; Czechowski, et al. 2002: 37; Bračko, 2006: 137; Cagnaint, 2006a: 197; Bračko, 2007: 17; Seifert, 2007: 214; Werner & Wiezik, 2007: 140, 147; Zryanin & Zryanina, 2007: 231; Wetterer, et al. 2007: 14; Gratiashvili & Barjadze, 2008: 139; Casevitz-Weulersse & Galkowski, 2009: 489; Lapeva-Gjonova, et al. 2010: 15; Boer, 2010: 61; Csösz, et al. 2011: 56; Legakis, 2011: 11; Borowiec, L. & Salata, 2012: 515; Czechowski, et al. 2012: 119; Borowiec, L. 2014: 112; Radchenko, 2016: 171; Steiner, Csösz, et al. 2018: 399 (redescription).
 * Senior synonym of aedificator: Mayr, 1855: 464; Smith, F. 1858b: 162; Mayr, 1863: 397; Roger, 1863b: 29; André, 1874: 203 (in list); Forel, 1874: 101 (in list); Emery & Forel, 1879: 462; Dalla Torre, 1893: 105; Emery, 1921f: 73; Bolton, 1995b: 252; Radchenko, 2016: 171; Steiner, Csösz, et al. 2018: supplementary material, 6.
 * Senior synonym of darianus: Dlussky, Soyunov & Zabelin, 1990: 224; Radchenko, 2016: 171.
 * Senior synonym of jakowlevi: Dlussky, Soyunov & Zabelin, 1990: 224; Radchenko, 2016: 171.
 * Senior synonym of lapidum: Nylander, 1856b: 85; Smith, F. 1858b: 162; Smith, F. 1861a: 35; Mayr, 1863: 397; Roger, 1863b: 29; Forel, 1874: 100 (in list); Emery & Forel, 1879: 462; Dalla Torre, 1893: 105; Ruzsky, 1905b: 728; Emery, 1921f: 73; Bolton, 1995b: 257; Radchenko, 2016: 171; Steiner, Csösz, et al. 2018: 399.
 * Senior synonym of romanus: Dlussky, Soyunov & Zabelin, 1990: 224; Bolton, 1995b: 257.
 * Senior synonym of rubella: Dlussky, Soyunov & Zabelin, 1990: 224; Radchenko, 2016: 171.
 * Senior synonym of rufitarsis Fabricius: Nylander, 1856b: 85; Smith, F. 1858b: 162; Mayr, 1863: 397; Roger, 1863b: 29; Forel, 1874: 101 (in list); Emery & Forel, 1879: 462; Nasonov, 1889: 37; Dalla Torre, 1893: 105; Ruzsky, 1905b: 728; Emery, 1921f: 73; Agosti & Collingwood, 1987a: 54; Casevitz-Weulersse, 1990a: 154; Atanassov & Dlussky, 1992: 115; Bolton, 1995b: 256; Gratiashvili & Barjadze, 2008: 139; Csösz, et al. 2011: 56; Radchenko, 2016: 171; Steiner, Csösz, et al. 2018: 399.
 * Senior synonym of subpolitus: Dlussky, Soyunov & Zabelin, 1990: 224; Radchenko, 2016: 171.
 * Senior synonym of turanicus: Dlussky, Soyunov & Zabelin, 1990: 224; Bolton, 1995b: 257; Radchenko, 2016: 171.
 * Current subspecies: nominal plus platyceras, tyrrhenus.
 * lapidum. Formica lapidum Fabricius, 1804: 407 (w.) AUSTRIA.
 * Combination in Aphaenogaster: Roger, 1863b: 29.
 * Junior synonym of rufitarsis Fabricius: Emery, 1921b: 211.
 * Junior synonym of structor: Nylander, 1856b: 85; Smith, F. 1858b: 162; Smith, F. 1861a: 35; Mayr, 1863: 397; Roger, 1863b: 29; Forel, 1874: 100 (in list); Emery & Forel, 1879: 462; Dalla Torre, 1893: 105; Ruzsky, 1905b: 728; Emery, 1921f: 73; Bolton, 1995b: 255; Radchenko, 2016: 171; Steiner, Csösz, et al. 2018: 399.
 * rufitarsis. Formica rufitarsis Fabricius, 1804: 406 (w.) AUSTRIA.
 * Combination in Aphaenogaster: Roger, 1863b: 29.
 * Combination in Messor: Emery, 1921b: 211.
 * Subspecies of barbarus: Emery, 1921b: 211.
 * Subspecies of structor: Santschi, 1926f: 290; Santschi, 1927d: 247; Menozzi, 1933b: 54; Santschi, 1934d: 275; Santschi, 1939c: 6; Pisarski, 1975: 16.
 * Status as species: Röszler, 1942a: 51; Röszler, 1942b: 32; Röszler, 1951: 88; Bernard, 1955a: 361 (in key); Bernard, 1956b: 258; Baroni Urbani, 1964b: 41; Pisarski, 1967: 383; Bernard, 1967: 144 (redescription); Kutter, 1968a: 59; Pisarski, 1970: 306; Arnol’di, 1970a: 79; Tarbinsky, 1976: 54; van Boven, 1977: 88; Baroni Urbani, 1971c: 63; Kutter, 1977c: 82; Arnol'di, 1977b: 1643 (in key); Arnol'di & Dlussky, 1978: 537 (in key); Bernard, 1981b: 143.
 * Junior synonym of structor: Nylander, 1856b: 85; Smith, F. 1858b: 162; Smith, F. 1861a: 35; Roger, 1863b: 29; Mayr, 1863: 397; Emery & Forel, 1879: 462; Nasonov, 1889: 37; Emery, 1921f: 73; Agosti & Collingwood, 1987a: 54; Casevitz-Weulersse, 1990a: 154; Bolton, 1995b: 256; Steiner, Csösz, et al. 2018: 399.
 * aedificator. Formica aedificator Schilling, 1839: 56 (w.) POLAND.
 * [Misspelled as aedificans by Mayr, 1855: 464, Smith, F. 1858b: 162.]
 * Combination in Aphaenogaster: Roger, 1863b: 29.
 * Junior synonym of rufitarsis Fabricius: Emery, 1921b: 211; Pisarski, 1975: 16.
 * Junior synonym of structor: Mayr, 1855: 464; Smith, F. 1858b: 162; Mayr, 1863: 397; Roger, 1863b: 29; André, 1874: 203 (in list); Forel, 1874: 101 (in list); Emery & Forel, 1879: 462; Dalla Torre, 1893: 105; Emery, 1921f: 73; Bolton, 1995b: 252; Radchenko, 2016: 171; Steiner, Csösz, et al. 2018: supplementary material, 6.
 * rubella. Messor platyceras var. rubella Crawley, 1920a: 164 (s.w.m.) IRAN.
 * Junior synonym of clivorum: Emery, 1921b: 210 (footnote); Bolton, 1995b: 256 (error).
 * Junior synonym of structor: Dlussky, Soyunov & Zabelin, 1990: 224; Radchenko, 2016: 171.
 * turanicus. Messor structor subsp. turanicus Kuznetsov-Ugamsky, 1927a: 91 (in key) (w.) UZBEKISTAN.
 * Subspecies of structor: Kuznetsov-Ugamsky, 1929d: 14.
 * Synonym of darianus: Santschi, 1927d: 247; Pisarski, 1967: 383; Pisarski, 1970: 306; Tarbinsky, 1976: 54; Arnol'di, 1977b: 1644.
 * [Note: Santschi, Pisarski, Tarbinsky, and Arnol’di all give darianus as senior synonym, but turanicus has priority (Bolton, 1995b: 258).]
 * Junior synonym of structor: Dlussky, Soyunov & Zabelin, 1990: 224; Bolton, 1995b: 258; Radchenko, 2016: 171.
 * darianus. Messor rufitarsis subsp. darianus Pisarski, 1967: 383 (w.) UZBEKISTAN.
 * [First available use of Messor structor st. rufitarsis var. darianus Santschi, 1926f: 291 (w.) UZBEKISTAN; unavailable (infrasubspecific) name.]
 * [Misspelled as dariagus by He & Song, 2009: 724.]
 * As unavailable (infrasubspecific) name: Santschi, 1927d: 247; Kuznetsov-Ugamsky, 1929d: 22.
 * Material referred to structor by Kuznetsov-Ugamsky, 1927a: 92 (in key).
 * Subspecies of rufitarsis Fabricius: Tarbinsky, 1976: 54; He & Song, 2009: 724.
 * Synonym of turanicus: Santschi, 1927d: 247; Pisarski, 1967: 383; Pisarski, 1970: 306; Tarbinsky, 1976: 54; Arnol'di, 1977b: 1644 (in key).
 * [Note: Santschi, Pisarski, Tarbinsky, and Arnol’di, all give darianus as senior synonym, but turanicus has priority (Bolton, 1995b: 253).]
 * Junior synonym of structor: Dlussky, Soyunov & Zabelin, 1990: 224; Radchenko, 2016: 171.
 * jakowlevi. Messor rufitarsis subsp. jakowlevi Arnol'di, 1977b: 1643 (w.) UKRAINE.
 * [First available use of Aphaenogaster (Messor) barbarus subsp. capitatus var. jakowlevi Ruzsky, 1905b: 750 (w.) UKRAINE; unavailable (infrasubspecific) name.]
 * [Misspelled as jakovlevi by Arnol’di & Dlussky, 1978: 537 (in key).]
 * As unavailable (infrasubspecific) name: Emery, 1908e: 450; Emery, 1921f: 72; Emery, 1922c: 96; Karavaiev, 1927a: 287.
 * Subspecies of rufitarsis Fabricius: Arnol’di & Dlussky, 1978: 537 (in key); Steiner, Csösz, et al. 2018: supplementary material, 8 (nomen dubium).
 * [Note: because Steiner, Csösz, et al. 2018: 399, establish rufitarsis Fabricius as a junior synonym of structor, the synonymy of jakowlevi under structor, below, still stands.]
 * Junior synonym of structor: Dlussky, Soyunov & Zabelin, 1990: 224; Atanassov & Dlussky, 1992: 114; Bolton, 1995b: 254.
 * Material of the unavailable name salina referred here by Arnol'di, 1977b: 1643 (in key).
 * subpolitus. Messor structor var. subpolitus Kuznetsov-Ugamsky, 1927a: 92 (in key) (w.) KYRGYZSTAN, UZBEKISTAN.
 * Subspecies of structor: Kuznetsov-Ugamsky, 1929d: 15.
 * Junior synonym of clivorum: Tarbinsky, 1976: 56; Bolton, 1995b: 257.
 * Junior synonym of structor: Dlussky, Soyunov & Zabelin, 1990: 224; Radchenko, 2016: 171.

Taxonomic Notes
Salata & Borowiec (2019) (misidentification):
 * As Messor cf. clivorum: Borowiec and Salata, 2018a: 7.

Description
Steiner et al. (2018) - Worker and queen. Colour: Head and mesosoma brown to brownish red, gaster brown; major workers sometimes entirely dark brown. Size: Medium. Head: Mostly costate entirely. Parallel costae below eye level. Especially in major and medium worker, vertex or even entire surface above eye level with irregular costae and costulae with microreticulation amongst. In minor and sometimes in media worker, costae reduced in postocular region; head almost smooth and frequently shining, with only fine costulae and microreticulate. Erect setae abundant on side of head from occiput to mandibular insertion. Scape: Base with rounded, laterally-downward directed lobe, very distinct in minor worker; can be reduced in major worker. 1st funicular segment long and flattened, almost as long as 2nd and 3rd segment together. Clypeus: Median notch well defined; can be shallow in minor worker. Pronotum: Middle mostly coarsely and irregularly costate throughout. Mesonotum: Coarsely and irregularly costate throughout. Mesopleuron: Coarsely sculptured with irregular transverse costae, with shallow punctuation among costae. Minor workers less costate with almost no punctuation. Propodeum: Mostly smoothly rounded; often obliquely rounded or rarely angled in major workers. Surface of 1st gaster tergite: Basis imbricate, middle with isolated snow-flakes-like structure. Covered with yellowish, thin, sparse hairs, some of which decumbent and subdecumbent in some individuals.

Queen: Metanotum: coarsely costate. Anepisternum and katepisternum: Middle shining and smooth, side with longitudinal costulae.

Male: Anepisternum: Shining, but often microreticulate. Katepisternum: Microreticulate, side with few costulae.

Type Material


Steiner et al. (2018) - 9 additional workers from the same nest series and labelled as the neotype are deposited in NHMW (5 workers) and in (4 workers). If neotype is destroyed or lost, a replacement neotype can be designated from these 9 workers.