Subfamily PONERINAE
Tribe PONERINI
Odontomachus bauri Emery , 1892

Odontomachus bauri, profile view of worker (click image to enlarge).
Photo courtesy of http://www.antweb.org/

Odontomachus bauri, profile view of a queen (click image to enlarge).
Photo courtesy of http://www.antweb.org/

Introduction
Ants in this genus differ from other ponerine ants found in the United States by the unique head shape; peculiar mandibles, which are elongate and inserted near the center of the clypeus (see photo above); the large tapering petiole; and the large size of the workers. Members of this genus are commonly called trap-jaw ants due to their elongate mandibles, which can be opened to 180°, then snapped rapidly together on prey. These ants are amazing in their ability to control and time the mandibular movement. When necessary, an ant can forcibly close the mandibles against a surface or other organism and actually propel itself away for up to several inches! Remarkable behavior. Additionally, they can use the mandibles for much more sensitive movements such as caring for larvae or nest building.

Taxonomic History (from Barry Bolton, 2012)
Described as Odontomachus bauri Emery (1892); considered a subspecies of Odontomachus haematodus by Emery (1911); revived as a species by Taylor and Wilson (1962).

Identification
Worker: (from Brown 1976; Longino 1999). Color: piceus with legs dark yellowish-brown to dark reddish-brown. Length approximately 8-8.5 mm. Scape extends beyond the posterior region of head by about the length of the first funicular segment. Pronotum with transverse striae posteriorly. Petiole dome shaped (as seen from the side) and with transverse striae on sides and back. Gaster with fine appressed pubescence separated by at least one-fourth the length of each hair.

Males: (from AntWeb)
Head and thorax yellow to yellowish-brown with three black stripes on pronotal dorsum; propodeum, petiole, and gaster brownish-black, and antennae and legs pale yellowish-brown. Ocelli not on a conspicuous turret (as in some species), with each ocellus less than two-thirds as wide as the ocelllo-ocular space. Petiole strongly rugose laterally.

Biology and Economic Importance
Similar to other members of this subfamily, Odontomachus workers have a prominent sting(er), and have the ability to inflict a relatively painful sting.

According to Brown (1976), this species can tolerate drier conditions than other species in the genus.

Distribution
Brown stated that this species was known from tropical South and Central America, Galapagos, and the West Indies except Cuba and Bahamas. There have been anecdotal reports of this species along the Gulf Coast in the US, but I am unaware of any verified records at this time. I include this species here because it is certainly a likely possibility, especially in southern Florida.

Literature Cited
Bolton, B. 2012. Bolton World Catalog Ants. accessed on October 2012. [Available online: http://www.antweb.org/world.jsp]

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. Studia Entomol. 19:67-171.

Emery, C. 1892(1891). Voyage de M. Ch. Alluaud dans le territoire d'Assinie. Formicides. Annls Soc. Entomol. Fr. 60:553-574.

Emery, C. 1911e. Hymenoptera. Fam. Formicidae. Subfam. Ponerinae. Genera Insectorum 118:1-125.

Longino, J. 1999. Ants of Costa Rica: Odontomachus bauri Emery 1892. Online at: http://academic.evergreen.edu/projects/ants/genera/odontomachus/species/bauri/bauri.html (accessed on 11 October 2012).

Taylor, R. W. and Wilson, E. O. 1962 ("1961"). Ants from three remote oceanic islands. Psyche (Cambridge) 68:137-144.

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