Strumigenys shattucki

Identification
Bolton (2000) - A member of the Strumigenys anderseni-group. S. shattucki is a very distinctive member of this group of small Strumigenys species. Characters quickly differentiating it from Strumigenys anderseni and Strumigenys peetersi are tabulated under the former name.

Apart from the tabulated characters the mandibles of shattucki are distinct from the other known species of the group as their outer margins are more broadly convex basally and the blades more strongly down-curved. In full-face view the outer margins of the closed mandibles of shattucki diverge from the apex toward the clypeus, but close to the clypeal margin the outer borders pass through a rounded angle and the sides become almost parallel for a short di stance before intersecting the clypeal margin. In anderseni and peetersi the outer margins continue to diverge evenly from apex to clypeal margin. In the last two species the down-curvature of the mandible blades is even and gradual in full-face view, but in shattucki the down-curvature starts more abruptly, at the level of the diastema between the basal lamella and basal tooth.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  shattucki. Pyramica shattucki Bolton, 2000: 475 (w.) AUSTRALIA. Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 128

Worker
Holotype. TL 1.8, HL 0.46, HW 0.34, CI 74, ML 0.09, MI 20, SL 0.20, SI 59, PW 0.23, AL 0.47. In full-face view the rectangular basal lamella of the mandible is exposed for most of its length even when the mandibles are fully closed. Diastema between basal tooth and lamella minute, the mandible blade beginning its down-curvature at this level. Clypeal dorsum smooth, with appressed very narrowly spatulate hairs. Cephalic dorsum finely shagreenate, with an unsculptured smooth patch posteromedially. Ground pilosity of cephalic dorsum of somewhat larger appressed spatulate hairs than are present on the clypeus, but without standing hairs of any form. Upper scrobe margin and lateral margin of occipital lobe in full-face view with closely appressed short spatulate hairs, without laterally projecting pilosity. Eye with 4-5 large ommatidia in the longest row, with fewer than 20 ommatidia in total. Cuticle within antennal scrobe smooth and shining. Scape in dorsal view short and extremely broad, only 3.5 times longer than broad; at its widest the scape is equal in width to the apical antennal segment. Leading edge of scape with minute appressed hairs only. Pronotal humeri without specialised projecting hairs. Dorsal alitrunk without standing hairs but with sparse ground-pilosity of decumbent to appressed short spatulate hairs present. Alitrunk smooth and shining. Propodeum without trace of spines or teeth. Spongiform lamella of propodeal declivity forming a broad lobe, in profile its upper surface sloping downward posteriorly and following the slope of the propodeal dorsum; lobe broadest below level of spiracle. Petiole, postpetiole and gaster without standing hairs but both waist segments with posteriorly directed reclinate spatulate hairs, best developed at the posterior margins of the segments. Petiole node in dorsal view broader than long, petiole and disc of postpetiole unsculptured dorsally. Basigastral costulae short and weakly developed, with a median basal clear area where costulae are absent.

Paratype. TL 1.7, HL 0.44, HW 0.34, CI 77, ML 0.08, MI 18, SL 0.20, SI 59, PW 0.22, AL 0.46.