Myrmoteras

Myrmoteras is unique among the Formicinae in having the mandibles specialized as trap-jaws. This feature has evolved independently several times in ants and is also found in the ponerines Odontomachus and Anochetus, as well as a number of myrmicine genera. Species are found largely in forested areas where they forage singly on the surface of the ground and in leaf litter. Nests are small, with a single queen and a handful of workers, often in small twigs on the ground. These ants are relatively rare, or at least uncommonly encountered. The genus is primarily Oriental, occurring from India to the Philippines, Sulawesi and Lombok but is especially rich in Borneo and Sulawesi.

Identification
Ward et al. (2016) - An isolated genus in its subfamily with numerous distinctive features including elongate, trap-jaw mandibles and very large eyes.

Distribution
Primarily an Oriental distribution from India to the Philippines, Sulawesi, and Lombok of the Lesser Sunda Islands; limited to the east by Weber’s Line (Zettel and Sorger 2011).

China, India, Sri Lanka, Borneo, Indonesia, Philippines

Species richness
Species richness by country based on regional taxon lists (countries with darker colours are more species-rich). View Data



Biology
Species of the genus Myrmoteras Forel, 1893 are among the most bizarre ant forms and unique among Formicinae by having mandibles that form into a specialized trap-jaw mechanism – a character that, however, has convergently evolved in other subfamilies (Odontomachus and Anochetus in Ponerinae; Dacetini in Myrmicinae). The small Myrmoteras ants with cryptic living habits in leaf litter have been rarely collected in the past, although more specialized collecting methods have yielded a relatively high species diversity, especially on Borneo and Sulawesi (Agosti 1992).

Castes
Queen-worker dimorphism in body size is exceedingly small, and so is ovarian dimorphism (4 vs. 2 ovarioles). Flight thorax of queens has a large pronotum (dorsum of first segment), indicating worker-like neck muscles, hence queens are able to hunt during independent foundation (non-claustral ICF).



Nomenclature
Taxonomic history
 *  MYRMOTERAS [Formicinae: Myrmoteratini]
 * Myrmoteras Forel, 1893f: 607. Type-species: Myrmoteras binghamii Forel, 1893f: 608, by monotypy.
 * [Myrmoteras also described as new by Forel, 1894c: 418.]
 * Myrmoteras in Camponotinae: Forel, 1894c: 420; Emery, 1896e: 187; in Camponotinae, Myrmoteratini: Emery, 1895j: 772; Wheeler, W.M. 1910g: 143; Forel, 1917: 248; in Gesomyrmicinae, Myrmoteratini: Ashmead, 1905b: 384; in Formicinae, Myrmoteratini: Wheeler, W.M. 1922a: 694; Emery, 1925b: 36; subsequent authors; in Oecophylla genus group: Agosti, 1991: 295.
 * Myrmoteras as genus: all authors.
 * Subgenera of Myrmoteras: nominal plus Myagroteras.
 * Myrmoteras catalogues: Emery, 1925b: 36; Chapman & Capco, 1951: 209 (Asia); Bolton, 1995b: 287.
 * Myrmoteras references: Bingham, 1903: 313 (diagnosis); Emery, 1925b: 36 (diagnosis); Creighton, 1930a: 184 (all species key); Wheeler, W.M. 1933e: 75 (all species key); Gregg, 1954: 25 (all species key); Moffett, 1985b: 17 (diagnosis, all species revision, key); Dlussky & Fedoseeva, 1988: 77 (synoptic classification); Agosti, 1992: 405 (diagnosis, review of genus, Malesian species key); Bolton, 2003: 23, 107 (diagnosis, synopsis); Zettel & Sorger, 2011: 62 (Philippines species key); Bui, et al. 2013: 545 (Indo-Chinese Peninsula species key); Bharti & Akbar, 2014d: 79 (India species key).

Bui et al 2013 - Myrmoteras is in the tribe Myrmoteratini Emery, 1895 (Bolton, 2003). Its geographical range is the Oriental region and the Austro-Malayan subregion of the Australian region (Moffett, 1985; Xu, 1998; Agosti, 1992; Zettel & Sorger, 2011). Creighton (1930) revised the genus for the first time, listing six species including two new species. Moffett (1985) recognised a total of 18 species including 10 new species in two morphologically distinct subgenera: Myrmoteras with seven species and the new subgenus Myagroteras with eleven species. Later Agosti (1992) revised the species in the Malay archipelago including the Malay peninsula south of the Kra isthmus, the Philippines, New Guinea, the Islands of New Britain and New Ireland, and added 13 new species. Xu (1998) described one new species from Yunnan province, southwestern China, and recently Zettel & Sorger (2011) revised the Philippine taxa, adding 2 new species, and gave a list of 34 valid species names from the whole range of the genus.