Tyrannomyrmex

In 2003, Fernández described a new genus and species, Tyrannomyrmex rex Fernández, from peninsular Malaysia based on a single specimen collected from leaf litter at Negri Sembilan, Pasoh Forest Reserve in 1994 (Fernández, 2003). Fernández was unable to place the new genus in any existing myrmicine tribe although several potential candidates were considered including the Adelomyrmicini and Solenopsidini. Without additional specimens or molecular data this genus was temporarily placed as incertae sedis within the subfamily Mmyrmicinae. Since then, a second species, T. dux Borowiec has been described based on a single specimen collected from leaf litter in southern India in 1999 (Borowiec, 2007). In addition, Brian Heterick recognized a single male collected from a light trap in the Philippines in 1965 as possibly representing an unknown male of Tyrannomyrmex.

Identification
The following morphological characters for the genus are summarized below:


 * Mandibles with two teeth in the masticatory border, apical and smaller subapical. No teeth onin the basal margin of the mandible.
 * Inner ventral margin of masticatory border of mandibles with setae. Setae can be normal or modified.
 * Clypeus devoid of carinae.   Foveolae may be present.
 * Palpal formula 2, 2.   Confirmed.
 * Compound eyes small, reduced to a few ommatidia.
 * Antennae 11-segmented with an ill-defined 3-segmented club.
 * Frontal carinae and antennal scrobes absent.
 * Mesosoma without grooves.
 * Propodeal lobes large and round.
 * Sting large and robust.

Key to Species
KEY TO WORKERS OF TYRANNOMYRMEX

1) Erect hairs on mesosomal dorsum very short, confined to anterior of pronotum, foveolae small and sparse, individual foveolae widely separated. Peninsular Malaysia => rex

- Dorsum of mesosoma with numerous long erect hairs scattered over the entire surface, foveolae large and dense, individual foveolae approximate to each other => 2

2) Petiole relatively slender, with node dorsum about as long as anterior slope when viewed from abovee without an anteroventral keel or lobe, postpetiole with an anteroventral spur or spine. India => dux

- Petiole with an anteroventral lobe, postpetiole without an anteroventral spur or spinemore robust, with node dorsum much longer than anterior slope when viewed from above. Sri Lanka => legatus

Nomenclature
Tyrannomyrmex has been unplaced to tribe within the subfamily Myrmicinae. However, recent unpublished molecular work (Marek Borowiec, personal communication) has placed this genus near Monomorium, thus belonging to the tribe Solenopsidini.