Australian species of the ant genus Dolichoderus (Hymenoptera: Formicidae) Author Shattuck, Steven O. Author Marsden, Sharon text Zootaxa 2013 3716 2 101 143 journal article 10.11646/zootaxa.3716.2.1 f685afba-b823-44c6-8ec9-f931fee7647a 1175-5326 248496 E76C890A-DC27-4B8A-90CD-41D10682E8FA Dolichoderus omicron sp. n. ( Fig. 18 ) Types . Holotype worker from Poochera, "Freightline site" just south of village, 32°43'S 134°50'E , South Australia , 10–13 November 1981 , R.W. Taylor & R.J. Bartell, nocturnal foragers, mallee woodland (ANIC, ANIC32- 066601); 5 paratype workers, same data as holotype except ANIC32- 061292 (ANIC); 6 paratype workers from Poochera, "Rubbish dump site" just north of village, 32°43'S 134°50'E , South Australia , 10–13 November 1981 , R.W. Taylor & R.J. Bartell, diurnal collection, mallee woodland (ANIC32- 061295 , 3 in ANIC, 3 in MCZC); 1 paratype worker from the Poochera area, " Nothomyrmecia original site", 32°43'S 134°50'E , South Australia , 13–17 November 1977 , R.W. Taylor & P.S. Ward, diurnal (ANIC, ANIC32- 061294 ); 2 paratype workers from Poochera, "collected in CSIRO enclosure", 32°43'S 134°50'E , South Australia , October–November, 1984, R.W. Taylor & R.J. Bartell, mallee woodland (ANIC, ANIC32- 061291 ); 1 paratype worker from Poochera, site "X" 2km S of village, 32°43'S 134°50'E , South Australia , 6–15 November 1982 , R.W. Taylor & R.J. Bartell, mallee woodland (ANIC, ANIC32- 061293 ). Diagnosis . 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; gaster yellowish red and lighter in colour than the mesosoma; with sparse pubescence on the first gastral tergite and hairs generally not overlapping or entirely absent; tibiae with erect or suberect hairs. This species is most similar to D. canopus but can be distinguished by having a gaster yellowish red and lighter in colour that the mesosoma whereas D. canopus has a gaster which is at least similar in colour if not darker than the mesosoma. Worker description . See Fig. 18 . Available specimens uniform and similar to the figured individual except in showing moderate variation in body colour, which varies from light reddish-brown to brown (as illustrated), and leg colour, which ranges from yellow-red to reddish-brown (as illustrated). FIGURE 18. Dolichoderus omicron , worker from Eucla, Western Australia (ANIC32-063771). A. Front of head; B. Side of body; C. Top of body; D. Distribution of material examined. Measurements (n=5). CI 82–87; EI 31–34; EL 0.24–0.28; HL 0.87–0.99; HW 0.72–0.86; ML 1.14–1.34; MTL 0.61–0.71; PronI 66.49–70.16; PronW 0.49–0.59; SI 112–119; SL 0.85–0.96. Material examined . New South Wales : 7mi . S Hillston (Lowery,B.B.) (ANIC); Bogan River (Armstrong,J.) (ANIC); South Australia : 10km S Yardea HS, Gawler Ranges (Greenslade,P.J.M.) (ANIC); 11mi . E Kimba (Greenslade,P.J.M.) (ANIC); 53km E Vokes Hill, Victoria Desert (Greenslade,P.J.M.) (ANIC); Blyth (Lowery,B.B.) (ANIC); Brookfield [Brookfield Conservation Park] (Greenslade,P.J.M.) (ANIC); Cambrai (Greenslade,P.J.M.) (ANIC); Ferries-McDonald Reserve, Monarto Sth. [Monarto South] (Greenslade,P.J.M.) (ANIC); Goondooloo (Crozier,R.C.) (ANIC); Inkster, SW Poochera (Casparson,K.) (ANIC); Mambray Creek, S Flinders Ranges (Greenslade,P.J.M.) (ANIC); Monarto Stn (Greenslade,P.J.M.) (ANIC); Poochera (Taylor,R.W. & Bartell,R.J.) (ANIC); Poochera area (Taylor,R. & Ward,P.) (ANIC); Sevenhill (Lowery,B.B.) (ANIC); Sinclair Gap (Barker,S.) (SAMA); Streaky Bay (Lowery,B.B.) (ANIC); Victoria : Wyperfeld National Park., Duttuck Tk. (Harvey,M.S. & Roberts,B.E.) (ANIC); Western Australia : 11 mi . E Pingrup (Greaves,T.) (ANIC); 19mi . NNW Widgiemooltha (Taylor,R.W.) (ANIC); 26mi . ENE Norseman (Taylor,R.W.) (ANIC); 3km S Wundowie (Ward,P.S.) (ANIC); Caiguna (Lowery,B.B.) (ANIC); Eucla (Shattuck,S.O.) (ANIC); York (Douglas,A.M. & Douglas,M.J.) (ANIC). Comments . Dolichoderus omicron is found in semi-arid open forested areas such as mallee woodlands and broombrush thickets across most of southern Australia . It forages during the day in columns primarily on the ground and nests in soil under rocks.