Odontomachus coquereli

A Madagascar endemic that forms small colonies of less than 50 workers.

Identification
The lone member of the Odontomachus coquereli group.

Distribution
Endemic to Madagascar.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Biology
Fisher and Smith (2008) - Restricted in Madagascar to eastern and northern montane rainforest, lowland rainforest, and littoral forest from 10 to 1325 m. It is most abundant at mid-elevations in the northeast such as in Marojejy National Park. Nests of Odontomachus coquereli are most commonly found in rotten logs and consist of small colonies. Queens of coquereli are wingless and very similar to workers; colonies reproduce by fission. Males are collected in Malaise traps and yellow pan traps. Workers forage on the ground day and night. Solitary foragers have been observed high up on trunks and branches of large trees. It is not clear if they are foraging for plant or insect liquids up in the canopy.

Odontomachus coquereli is the only species in the genus where winged queens have never been found. Molet et al. (2007) investigated the Marojejy population of O. coquereli, and based on demography, morphometry, allometry and ovarian dissections demonstrated that the winged queen caste has been replaced by a wingless reproductive caste and that the strategy of colonial reproduction is fission. A single wingless reproductive (ergatoid) was found in each colony. The smallest colonies consisted of at least 5 workers and the largest colonies never exceeded 40 workers, indicating a threshold size at which a colony divides in two daughter colonies. In contrast, Odontomachus troglodytes reproduces by non-claustral independent foundation and colonies can reach 1300 workers.

Nomenclature

 * . Odontomachus coquereli Roger, 1861a: 30 (w.) MADAGASCAR.
 * Type-material: lectotype worker (by designation of Fisher & Smith, 2008: 14).
 * Type-locality: Madagascar: (no further data) (Coquerel).
 * Type-depository: MNHU.
 * Fisher & Smith, 2008: 14 (q.m.).
 * Combination in Stenomyrmex: Mayr, 1865: 63 (footnote);
 * combination in Champsomyrmex: Emery, 1892d: 558;
 * combination in Odontomachus: Brown, 1976a: 103.
 * Status as species: Roger, 1863b: 21; Mayr, 1863: 436; Forel, 1891b: 105 (redescription); Dalla Torre, 1893: 49; Wasmann, 1897: 250; Emery, 1911d: 111; Wheeler, W.M. 1922a: 1013; Brown, 1976a: 103, 143; Bolton, 1995b: 295; Fisher & Smith, 2008: 14 (redescription).
 * Senior synonym of minor: Brown, 1976a: 103; Bolton, 1995b: 295; Fisher & Smith, 2008: 14.
 * Distribution: Madagascar.
 * minor. Champsomyrmex coquereli var. minor Emery, 1899f: 273 (w.q.) MADAGASCAR.
 * Type-material: lectotype worker (by designation of Fisher & Smith, 2008: 14).
 * Type-locality: Madagascar: Baie d’Antongil (A. Mocquerys).
 * Type-depository: MSNG.
 * Subspecies of coquereli: Forel, 1907g: 75; Emery, 1911d: 111; Wheeler, W.M. 1922a: 1013.
 * Junior synonym of coquereli: Brown, 1976a: 103; Bolton, 1995b: 296; Fisher & Smith, 2008: 14.

Worker
Fisher and Smith (2008) - Measurements: maximum and minimum based on n = 45 from Madagascar: HL 2.69–3.27, HW (across vertex) 1.26–1.77, HW (across upper eye margin) 1.54–2.02, CI 57–67, EL 0.46–0.55, ML 1.76–2.16, MI 61–68, SL 3.04–3.96, SI 164–207, WL 4.18–5.11. FL 3.32–4.68, PW 1.11–1.53.

Workers of this species can be easily distinguished from troglodytes by their larger size, mandible with long, acute apical and preapical teeth and lack of extraocular furrows and temporal ridges on vertex.

There is notable geographic variation in shape of petiole, sculpture and number of preapical teeth. Preapical teeth and denticles range from 7–12. Occasionally, adjacent teeth may be fused at base to form a single bidententate tooth. However, there is no consistent concordant pattern to this variation.

Queen
Fisher and Smith (2008) - Measurements: maximum and minimum based on n = 5 from Madagascar: HL 2.81–2.94, HW (across vertex) 1.39–1.55, HW (across upper eye margin) 1.83–1.98, CI 62–71, EL 0.45–0.55, ML 1.66–1.81, MI 59–62, SL 3.07–3.29, SI 155–179, WL 4.35–4.56, FL 3.60–3.84, PW 1.28–1.43. Preapical teeth count 7–10.

Male
Fisher and Smith (2008) - Measurements: maximum and minimum based on n = 5 from Madagascar: HL 1.11–1.22, HW 1.41–1.57, CI 128–134, EL 0.78–0.90, SL 0.30–0.38, SI 21–23, WL 3.38–3.85, FL 2.90–3.16.

Type Material
Fisher and Smith (2008):

Lectotype: worker, Madagascar (Coquerel), present designation [examined] AntWeb CASENT0104549. Odontomachus coquereli minor. Lectotype; worker, Madagascar, Baie d' Antongil (Mocquerys), present designation [examined] AntWeb CASENT0102021.

References based on Global Ant Biodiversity Informatics

 * Brown W. L., Jr. 1976. Contributions toward a reclassification of the Formicidae. Part VI. Ponerinae, tribe Ponerini, subtribe Odontomachiti. Section A. Introduction, subtribal characters. Genus Odontomachus. Stud. Entomol. 19: 67-171.
 * Emery C. 1899. Formiche di Madagascar raccolte dal Sig. A. Mocquerys nei pressi della Baia di Antongil (1897-1898). Bullettino della Società Entomologica Italiana 31: 263-290.
 * Fisher B. L. 1996. Ant diversity patterns along an elevational gradient in the Réserve Naturelle Intégrale d'Andringitra, Madagascar. Fieldiana Zoology (n.s.)85: 93-108
 * Fisher B. L. 1997. Biogeography and ecology of the ant fauna of Madagascar (Hymenoptera: Formicidae). Journal of Natural History 31: 269-302.
 * Fisher B. L. 1998. Ant diversity patterns along an elevational gradient in the Réserve Spéciale d'Anjanaharibe-Sud and on the western Masoala Peninsula, Madagascar. Fieldiana Zoology (n.s.)90: 39-67.
 * Fisher B. L. 2003. Formicidae, ants. Pp. 811-819 in: Goodman, S. M.; Benstead, J. P. (eds.) 2003. The natural history of Madagascar. Chicago: University of Chicago Press, xxi + 1709 pp.
 * Fisher B. L., and M. A. Smith. 2008. A revision of Malagasy species of Anochetus Mayr and Odontomachus Latreille (Hymenoptera: Formicidae). PLoS ONE 3(5): e1787. doi:10.1371/journal.pone.0001787
 * Forel A. 1897. Ameisen aus Nossi-Bé, Majunga, Juan de Nova (Madagaskar), den Aldabra-Inseln und Sansibar, gesammelt von Herrn Dr. A. Voeltzkow aus Berlin. Mit einem Anhang über die von Herrn Privatdocenten Dr. A. Brauer in Marburg auf den Seychellen und von Herrn Perrot auf Ste. Marie (Madagaskar) gesammelten Ameisen. Abhandlungen der Senckenbergischen Naturforschenden Gesellschaft 21: 185-208.
 * Molet, M., C. Peeters and B.L. Fisher. 2007. Permanent loss of wings in queens of the ant Odontomachus coquereli from Madagascar. Insectes Sociaux 54:183-188
 * Wheeler W. M. 1922. Ants of the American Museum Congo expedition. A contribution to the myrmecology of Africa. IX. A synonymic list of the ants of the Malagasy region. Bulletin of the American Museum of Natural History 45: 1005-1055