Odontomachus relictus, full face view of a worker (click image to enlarge).
Photo courtesy of http://www.antweb.org/

Odontomachus relictus, dorsal view of a worker (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 or snapping 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 (provided by Barry Bolton, 2012)
Described as Odontomachus relictus Deyrup and Cover, 2004.

Identification
Worker: (Deyrup and Cover 2004). Color: head, antennae, mesosoma, petiole dark reddish-brown with gaster blackish-brown and legs dark orangish-yellow. Length approximately 7.5 mm. Pronotum with transverse striae posteriorly. Petiole lacking transverse striae on posterior side. Basalar lobe with conspicuous striae present. Inner side of hind femur glabrous at base. Pubescence of first gastral tergite sparse, short, with spaces between hairs about as wide as length of hairs.

Males: (from Deyrup and Cover 2004)
Medium brown with yellowish antennae and legs. Approximately 6.7 mm in length. Ocelli on a conspicuous turret; each ocellus large, wider than the ocelllo-ocular space.

Workers are small to average in size for the genus, lack transverse striae on petiole, have relatively sparse gastral pubescence, and have striae present on the basalar lobe. Males are dark brown with large raised ocelli. A western species, O. clarus, is similar in appearance but workers lack striations on the basalar lobe and males have small ocelli that are not obviously raised.

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.

This species nests in deep sand in scrub type habitat in sand ridges in south-central Florida.

Distribution
Only known to occur in south-central peninsular FL (Highlands, Polk, and Orange Counties). 

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

Deyrup, M. and S. Cover. 2004.  A new species of Odontomachus ant (Hymenoptera:  Formicidae) from inland ridges of Florida, with a key to Odontomachus of the United States.  Florida Entomologist 87: 136-144.

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