Lophomyrmex Emery

Eguchi, K., Viet, B. T. & Yamane, S., 2011, Generic synopsis of the Formicidae of Vietnam (Insecta: Hymenoptera), Part I - Myrmicinae and Pseudomyrmicinae., Zootaxa 2878, pp. 1-61 : 17-18

Lophomyrmex Emery , 1892

Taxonomy. The genus Lophomyrmex was placed in the tribe Solenopsidini by Emery (1895), and in the Pheidologeton genus group by Ettershank (1966). More recently the genus was revised by Rigato (1994a), and transferred into the tribe Pheidolini . The worker of the single known Vietnamese species has the following features.

Worker monomorphic; head in full-face view oval with a relatively straight posterior margin; frontal carina and antennal scrobe absent; median portion of clypeus convex anteriad, with a protruding blunt tooth at the midpoint of its anterior margin; frontal lobes moderately separated by posteromedian portion of clypeus; antenna 11-segmented with distinct 3-segmented club; eye oval with a weak anteroventral point, located at about midlength of head in full-face view; masticatory margin of mandible with apical tooth and one preapical tooth, followed by an enlarged denticle, this then followed by a series of small denticles; basal margin of mandible finely serrated; promesonotum forming a single dome, flattened dorsally, with a pair of horizontal flat spines those are formed by the lateral and anterolateral edges of the dorsum and directed anteriad; promesonotal suture absent; metanotal groove well defined; propodeal spine long; propodeal lobe reduced to a weak carina; petiole with a distinct peduncle and a high node; gastral shoulder distinct.

The worker of Lophomyrmex is similar to the minor workers of Pheidole and Pheidologeton . However, in the minor worker of Oriental species of Pheidole , the antenna is 12-segmented and basal margin of the mandible is never serrated. In the worker of Pheidologeton the antennal club is 2-segmented and the basal margin of mandible is never serrated.

Vietnamese species. The genus Lophomyrmex occurs in the Oriental and Indo-Australian regions, and in Vietnam only one species has been found from the central and southern regions: birmanus Emery [= sp. eg-1] (Binh Chau-Phuoc Buu, Nam Cat Tien, Nui Chua).

Bionomics. Lophomyrmex birmanus nests in the soil, usually under stones and logs or around the bases of trees. Workers are active ground-foragers. We have collected workers by underground bait-trapping, suggesting they workers forage both on and under the ground.