Colobopsis badia

A canopy nesting species that is a member of the Colobopsis cylindrica group, a set of species that employ a novel defensive strategy. Minor workers of these so called exploding ants will, when threatened, flex their gasters so hard that they rupture. This releases a toxic chemical mixture that they then attempt to smear on their antagonists.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Indonesia, Malaysia, Singapore. Oriental Region: India.

Biology
Zettel et al. (2018) examined foraging ecology of this species and Colobopsis leonardi. Workers of a C. badia colony were observed on leaves of low vegetation and on lianas leading up to two small trees (Figure 2). Nest entrances were not found; they were most probably located higher up in the tree, as is often the case in COCY colonies. Feeding experiments were carried out on June 6, at around 10:30 a.m. when a moderately high activity of workers (higher than on the previous and following days) was observed on an ant trail on a ca. 2 cm thick liana ca. 0.5 m above ground. As a preliminary feeding experiment, three freshly killed specimens of Coptotermes curvignathus termites were placed on the liana at a distance of ca. 5 cm from each other. Workers approaching this area shrunk back without touching the C. curvignathus specimens and/or alarmed nest mates with highly raised gasters. The area was subsequently avoided by most (not all) workers which then used a liana running parallel to the first one. During the time of observation, a C. badia worker was observed carrying a small item. Worker and item were caught and preserved. The item was a very small male ant (presumably Dolichoderinae).

Nomenclature

 *  badia. Formica badia Smith, F. 1857a: 54 (w.) SINGAPORE. Viehmeyer, 1916a: 161 (m.). Combination in Camponotus: Roger, 1863b: 3; in C. (Colobopsis): Forel, 1913k: 133. [Unresolved junior primary homonym of Formica badia Latreille, 1802c: 238 (now in Pogonomyrmex (Bolton, 1995b: 87).] Current subspecies: nominal plus saginatus. Combiniation in Colobopsis: Ward, et al., 2016: 350.

Formica badia

Three worker syntypes in. One labelled “Sing. 6,” two labelled “Sar. 32.” Smith records both localities in the original description. There is also a single worker from Sumatra, det. as badia by Smith.