Gauromyrmex

Bolton (2003 p 269) states there are a number of undescribed species in the British Museum. Also: “all known species are arboreal and are size variable to weakly polymorphic.” Most of what is known about the two species are anecdotal reports: Gauromyrmex acanthinus - This ant appears to be rather common in India and China, and I believe that I have seen it on several occasions in Bengal Province nesting under loose bark, though the actual specimens were lost in a wartime shipment. In life, the distinctive point of recognition lies in the extremely depressed appearance of the ant, even when moving about. It appears to the naked eye somewhat like a flattened Leptothorax, and its attachment to tree trunks and plant cavities may be correlated with the habitus. (Brown 1953); Gauromyrmex bengakalisi - The species description states that collections of this ant were made in the forest and their nests were built in “resin trees” (presumably the common species Styrax benzoin).

Identification
Small workers, brown with darker gaster. Similar to Vollenhovia but with 11-segmented antennae and a bidentate propodeum. Vollenhovia possess a 12-segmented antennae and an unarmed, or at most just slightly toothed, propodeum.

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



Nomenclature

 *  GAUROMYRMEX [Myrmicinae: Formicoxenini]
 * Gauromyrmex Menozzi, 1933c: 146. Type-species: Gauromyrmex bengakalisi, by monotypy.
 * Gauromyrmex senior synonym of Acalama, Solenomyrma: Brown, 1953c: 10.
 * Gauromyrmex junior synonym of Vollenhovia: Hölldobler & Wilson, 1990: 16; Bolton, 1994: 105.
 * Gauromyrmex revived from synonymy: Bolton, 2003: 246, 269.
 * ACALAMA [junior synonym of Gauromyrmex]
 * Acalama Smith, M.R. 1949a: 206. Type-species: Acalama donisthorpei (junior synonym of Solenomyrma acanthina), by original designation.
 * Acalama junior synonym of Gauromyrmex: Brown, 1953c: 10.
 * SOLENOMYRMA [junior synonym of Gauromyrmex]
 * Solenomyrma Karavaiev, 1935a: 103. Type-species: Solenomyrma acanthina, by monotypy.
 * Solenomyrma junior synonym of Gauromyrmex: Brown, 1953c: 10.

Description
Smith (1949), as Acalama - Worker. Small, apparently monomorphic. Head (including mandibles) subcordate, with rounded posterior corners and not very deep, but distinctly emarginate posterior border. Antenna ll-segmented; with a prominent 3-segmented club, the latter much longer than the remainder of the funiculus; scape short, curved basally, enlarged apically, failing by one-fourth to one-third its length from reaching the posterior border of the head. Frontal carinre short, well-separated, indistinctly or not lobed, concealing antennal insertions. Frontal area indistinct or absent. Clypeus, in profile, flattened, median region extended as a short lobe, the anterior border of which is straight or indistinctly emarginate. Eye well-developed, placed nearer the anterior than the posterior border of the head, with at least 7-9 ommatidia in its greatest length. Mandible of ordinary shape, the masticatory border with 2 large apical and 3 or 4 smaller basal teeth.

Thorax, in profile, flattened or weakly convex. Pronotum with a distinct humeral tooth. Promesonotal suture obsolescent. Mesoepinotum with a remarkably deep constriction. Epinotal spines unusually short, upwardly directed. Legs rather short, with greatly enlarged femora and tibiae; tibial spur of anterior leg well-developed, those of the middle and posterior legs vestigial or lacking. Petiole non-pedunculate; anterior and posterior faces of the node declivous, the two surfaces meeting to form a sharp, transverse carina which is distinctly emarginate; ventral surface of petiole with a tooth. Post-petiole slightly broader than long, also broader than the petiole. Gaster truncate basally, with distinct humeral angles.