Polyrhachis kohouti

Polyrhachis kohouti is currently known only from the type locality, based on 2 specimens collected when their nest was disturbed by overturning a log. The species appears to be uncommon because extensive ant collections throughout NE Arnhem Land conducted since 2003, including in the type locality, have failed to find this species again. The vegetation of the type location is open savanna woodland dominated by Eucalyptus oligantha with an understorey of dense grasses, on gently sloping, seasonally waterlogged, loamy soil.

Identification
Polyrhachis kohouti can be easily recognised by the form of its petiole which has a deeply medially concave dorsum and is armed with rather massive, bull horn-shaped spines. The petiole in lateral view is relatively slender, in contrast to other species of the penelope-group where the posterior face of the petiole is usually more-or-less convex or distinctly swollen. Other distinguishing characters of P. kohouti include the strongly transverse pronotal dorsum with widely rounded humeri and strongly posteriorly converging lateral margins that are shallowly emarginate before terminating at the distinctly impressed promesonotal suture. The presence of numerous setae on most of the body surfaces also separates P. kohouti from other species of the penelope-group, which lack hairs, except Polyrhachis hoffmanni which has distinctly longer and sparser hairs on the body.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  kohouti. Polyrhachis (Hagiomyrma) kohouti Hoffmann, 2015: 54, figs. 1-4 (w.) AUSTRALIA.