Oligomyrmex

Oligomyrmex concinnus, copyright Alexandra Westrich.

Belongs within: Myrmicinae.

Oligomyrmex is a genus of ants characterised by a nine-segmented antenna with a relatively large, two-segmented club (Wheeler & Wheeler 1990).

Characters (from Bingham 1903): Queen: Head with mandibles scutiform or shield-shaped, posteriorly emarginate, sides convex, posterior lateral angles well marked though not prominent; mandibles broad, triangular, masticatory margin dentate, apical two teeth long and acute; clypeus not or only feebly bicarinate, its anterior margin more or less emarginate in the middle, truncate or obtusely angular posteriorly; frontal area distinct, triangular; antennae nine-segmented, club of flagellum formed of the apical two segments, of which the apical segment is very long, the club longer than the rest of the flagellum; eyes comparatively large and round, lateral, situated about the middle of the head. Thorax with pronotum rounded anteriorly, convex, not forming any portion of the dorsum; mesonotum broadening posteriorly, convex, but not gibbous; scutellum convex, slightly prominent; metanotum more or less vertical or steeply declivous, with or without a blunt tooth or tubercle on each side. Pedicel with first node shortly petiolate anteriorly, the petiole gradually thickening up to the node; second node more or less rectangular, often broader than long; gaster broadly oval, rather massive and bluntly rounded posteriorly. Fore wing with one rhomboidal cubital cell. Major worker resembling queen, but with the sexual differences in the shape of the thorax and gaster; clypeus bicarinate, the carinas convergent posteriorly, anteriorly not emarginate; antennae nine-segmented; eyes exceedingly small. Thorax with promesonotal suture obsolete, the pro-mesonotum forming a strong convexity; the thorax constricted and emarginate at the mesometanotal suture, which is strongly marked; basal portion of metanotum flat, rectangular, laterally submargined, a little longer than subvertical apical portion. Pedicel short, the first node shortly petiolate, transverse, flat anteriorly and posteriorly, with a distinct anterior and posterior margin above; second node rounded, transverse, about as broad as first node and (seen from above) a little longer; gaster very long and massive. Female minor resembling major but smaller and entirely without eyes, blind; antennae similar, apical segment in itself as long as remainder of flagelium. Head rounded posteriorly. Pedicel short, the nodes rounded, the anterior node not petiolate; abdomen small. Male with head more or less square; mandibles either dentate or pointed; antennae with 13 segments. Thorax shorter and broader than that of female, but similar to it. Pedicel with the nodes low and broad; abdomen smaller and narrower than in female. Wings as in female.

<==Oligomyrmex Mayr 1867 (see below for synonymy) Z01
    |--*O. concinnus Mayr 1867 TB85
    |--O. asinus Forel 1902 B03
    |--O. bengalensis Forel 1902 B03
    |--O. corniger Forel 1902 TB85
    |    |--O. c. corniger TB85
    |    |--O. c. parvicornis Forel 1915 TB85
    |    `--O. c. sodalis Emery 1914 E14
    |--O. cribriceps (Wheeler 1927) [=Aneleus cribriceps] Z01
    |--O. leei Forel 1902 B03
    |--O. longi [=Erebomyrma longi] WW90
    |--O. mjobergi Forel 1915 TB85
    |--O. norfolkensis Donisthorpe 1941 [=O. manni norfolkensis] TB85
    |--O. pachycerus Forel 1915 [=O. (*Octella) pachycerus] TB85
    |--O. raja Forel 1902 B03
    `--O. rothneyi Forel 1902 B03

Oligomyrmex Mayr 1867 [incl. Aeromyrmex Forel 1891, Aneleus Emery 1900, Crateropsis Patrizi 1948, Erebomyemex Wheeler 1903, Hendecatella Wheeler 1927, Lecanomyrmex Forel 1913, Nimbamyrmex Bernard 1953, Octella Forel 1915, Solenps Karavajew 1903, Spelaeomyrmex Wheeler 1922, Sporocleptes Arnold 1948] Z01

*Type species of generic name indicated

REFERENCES

[B03] Bingham, C. T. 1903. The Fauna of British India, including Ceylon and Burma. Hymenoptera vol. 2. Ants and Cuckoo-Wasps. Taylor and Francis: London.

[E14] Emery, C. 1914. Les fourmis de la Nouvelle-Calédonie & des îles Loyalty. In: Sarasin, F., & J. Roux (eds) Nova Caledonia: Forschungen in Neu-Caledonian und auf den Loyalty-Inseln. A. Zoologie vol. 1 pt 4 pp. 393–436, pl. 12. C. W. Kreidels Verlag: Wiesbaden.

[TB85] Taylor, R. W., & D. R. Brown. 1985. Formicoidea. In: Walton, D. W. (ed.) Zoological Catalogue of Australia vol. 2. Hymenoptera: Formicoidea, Vespoidea and Sphecoidea pp. 1–149. Australian Government Publishing Service: Canberra.

[WW90] Wheeler, G. C., & J. Wheeler. 1990. Insecta: Hymenoptera Formicidae. In: Dindal, D. L. (ed.) Soil Biology Guide pp. 1277–1294. John Wiley & Sones: New York.

[Z01] Zhou, S. 2001. Ants of Guangxi. Guangxi Normal University Press: Guilin (China).