Dolichoderus nigricornis

Dolichoderus nigricornis is one of the more widespread species, occurring across much of southern Australia. It is known from dry sclerophyll and riparian woodlands where it forages on trees. Nests are in soil under rocks.

Identification
Head reddish to reddish-brown and lighter in colour than dark brown to black gaster; sculpturing pattern of head and pronotum, with large but shallow and closely spaced foveae compared to the indistinct sculpturing pattern of D. canopus; pale markings absent from lower margin of the eyes; pronotum and propodeum lacking spines; in dorsal view the pronotum with only weakly defined shoulders, with the area between the shoulders more strongly convex to flat; dorsum of propodeum weakly and evenly convex, the length shorter (at most approximately the same length) than the posterior face, with a narrow carina separating the dorsal and posterior faces; posterior face of propodeum weakly concave, separated from the dorsal face by a distinct carina; mesosoma with both erect hairs and scattered appressed pubescence; gaster dark brown to black with scattered appressed pubescence; tibiae with erect or suberect hairs.

This species is most similar to Dolichoderus formosus but can be distinguished from D. formosus by having a head lighter in colour (reddish to reddish-brown) than the gaster (dark brown to black) compared to the similar coloured head and gaster (dark brown to black) in D. formosus, and in having scattered appressed pubescence on the mesosoma and gaster.

Key to Australian Dolichoderus Species

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  nigricornis. Dolichoderus (Hypoclinea) nigricornis Clark, 1930b: 264, fig. 14 (w.) AUSTRALIA.

Description
The available specimens show minor variation in leg colour, which varies from yellowish-red to reddish-brown, but otherwise all material is similar.

Measurements (n=5). CI 79–89; EI 31–35; EL 0.26–0.29; HL 0.92–1.03; HW 0.78–0.90; ML 1.25–1.41; MTL 0.67–0.75; PronI 67.26–71.66; PronW 0.53–0.61; SI 107–122; SL 0.91–1.00.

Additional References

 * Shattuck, S.O. & Marsden, S. 2013. Australian species of the ant genus Dolichoderus (Hymenoptera: Formicidae). Zootaxa 3716, 101–143 (doi 10.11646/zootaxa.3716.2.1).