Colobopsis explodens

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: Brunei Darussalam, Malaysia. Oriental Region: Thailand.

Biology
Laciny et al. (2018) observed "a peculiar guarding behaviour: a small number of workers always stayed close to the entrance and seemingly monitored the entering and leaving of foragers. It is possible that an ant carrying a potential enemy as prey would be barred from entering the nest by guards within and must therefore present its gaster to be recognized as a colony member.

Nomenclature

 *  explodens. Colobopsis explodens Laciny & Zettel, in Laciny et al., 2018: 10, figs. 2-9 (s.w.q.m.) BRUNEI.

Type Material
Paratypes: 59 minor workers, 8 major workers, 16 gynes, and 6 males dry mounted; > 500 imagines stored in 96 % ethanol (housed in Universiti Brunei Darussalam, the Natural History Museum Vienna, the University of California (Davis, USA), the Natural History Museum of Los Angeles County (Los Angeles, USA), the Thailand Natural History Museum (Technopolis, Thailand), and the collection of H. Zettel (Vienna, Austria)).
 * 19 minor workers, 2 major workers, 12 alate gynes, 4 dealate gynes, 6 males (including allotype) (all dry mounted), as well as 8 males, 2 alate gynes, ca. 500 minor workers (in alcohol) from the same nest sample as holotype
 * 1 major worker, same locality and collector as holotype, 17.IV.2015, “YG 373 main natural nest”
 * 1 major worker, same data as holotype (“YG doorkeeper #19”)
 * 2 major workers, same data as holotype except 20.IV.2015, leg. A. Kopchinskiy (“cf. YG 39 (351) artificial nest”)
 * 8 minor workers, 2 major workers, same locality as holotype, 2002, leg. D.W. Davidson (“YG KB02-108”)
 * 4 minor workers, same locality and collector as previous, no collection date, “YG 2025”
 * 5 minor workers, same locality and collector as previous, I.2012, “YG T-trail (202)”
 * 5 minor workers, same locality and collector as previous, 15.V.2014, “YG-2 (73)”
 * 7 minor workers, same locality and collector as previous, 15.V.2014, “YG-2 (49)”
 * 2 minor workers, same data as previous except Batu Apoi Forest Reserve, N04°32', E115°10', 200 m a.s.l., 25.XI.2004, (“CAYG A-370”)
 * 15 minor workers (on 5 pins), same data as previous, except N04°55', E115°19', 60 m, 3.VII.2002, (“YG KB02-108 voucher”)
 * 4 minor workers, Thailand, Chumphon Province, Krom Luang Chumphon W.S, 3.II.2002, leg. W. Jaitrong (“WJT02-TH-0116”)
 * 5 minor workers, West Malaysia, Kelantan, 60 km NE Tanah Rata, Tanah Kerajaan, 1000 m a.s.l., 12.–30.IV2007, leg. P. Cechovský.