Leptomyrmex burwelli, Smith, Derek J. & Shattuck, Steve, 2009

Smith, Derek J. & Shattuck, Steve, 2009, Six new, unusually small ants of the genus Leptomyrmex (Hymenoptera: Formicidae), Zootaxa 2142 (1), pp. 57-68 : 60-61

Leptomyrmex burwelli sp. n.

( Figs 4–6 , 19–21 , 23 )

Types. Holotype worker from Maiala National Park, Mt. D’Aguilar Range , Queensland, R.W.Taylor, 3 May 1962, under stone, rainforest ( ANIC: R.W.Taylor 62.753, ANIC Ants Vial 9/38, ANIC32-002908 ); six paratype workers, same data as holotype (2 each in AMSA, ANIC, QMBA).

Diagnosis. Scapes long (SI> 170, Fig. 20 ); pubescence of short, sparse adpressed hairs; dorsum of petiolar node strongly convex in anterior view; anterior mesonotum with a strongly raised bump ( Fig. 5 ).

Worker description. In full face view vertex of head weakly convex, rounding into sides of head, sides of head weakly rounded, widest at mid-length, eyes placed at mid-length of head capsule. Palps long extending about ¾ the length of the head capsule. Pronotum even with promesonotal suture, posterior margin of pronotum not rounding sharply to the suture; anterior portion of the mesonotum raised above the promesonotal suture then rounding sharply into descending plane of remainder of mesonotum producing a distinctive strongly raised anterior mesonotal “bump”. Legs long; hind tibial spurs with reduced barbules, barbules absent from basal one-quarter.

Queen description. As described in Shattuck (1992).

Male description. As described in Shattuck (1992), except the antenna lacks the distinctive bend between funicular segments 3 and 4.

Measurements. Worker (n = 117) - CI 69–79; EL 0.20–0.25; HL 0.79–0.97; HW 0.60–0.70; MTL 0.71–0.96; SI 171–200; SL 1.10–1.29; WL 1.2–1.4. Queen (n = 1) - CI 91; EL 0.38; HL 0.94; HW 1.03; HL 1.13; MTL 1.075; SI 139; SL 1.43; WL 1.95. Male (n = 3) - CI 74–76; EL 0.33–0.36; HL 0.60–0.67; HW 0.53–0.65; MTL 0.75–0.81; SI* 10; SL 0.23–0.25; WL 1.23–1.32.

* Only 2 of the available males had all funicular segments attached. SI in males is scape length relative to length of the funicular segments ( Shattuck, 1992).

Additional material examined. N ew South Wales: Breakfast Ck., Mt. Warning (Lowery,B.B.) (ANIC). Queensland: 7km NNW North Tamborine (Ward,P.S.) (ANIC); Boombana Nat. Park (Burwell,C.J.; Monteith,G.; QM Party; Wright,S.) (QMBA); c. Binna Burra (Taylor,R.W.) (ANIC); Cunninghams Gap (Greenslade,P.J.M.) (ANIC); Joalah NP, Mt. Tambourine (Taylor,R.W.) (ANIC); Lamington Nat. Park (Baehr,B., Grey,J. & Staunton,K.; Burwell,C.J.; Menendez,R. & Monteith,G.) (QMBA); Mary Cairncross Pk., nr. Maleny (Ward,P.S.) (ANIC); Miala NP (Taylor,R.W.) (ANIC); Mt. D'aguilar Ra., Miala NP [as Daguilar] (Taylor,R.W.) (ANIC); Mt. Glorious (Ward,P.S.; Wild,A.L.) (ANIC); Mt. Tamborine (Lowery,B.B.) (ANIC); Numinbah (Lowery,B.B.) (ANIC).

Comments. Leptomyrmex burwelli is restricted to rainforest where it is known to nest under rocks or less commonly in rotten wood. It forages on the ground as well as on vegetation. This species has so far only been found in the south-eastern corner of Queensland with one record just over the border in NSW. Given the trapping intensity of the NEFBS project it is thought unlikely that the range of this species will extend further into NSW. It can readily be separated from the sympatric L. aitchisoni by the distinctively humped anterior mesonotum.

Figures

FIGURES 1–6. Leptomyrmex aitchisoni sp. n. worker. Fig. 1, front of head; Fig. 2, lateral view of body; Fig. 3, dorsal view of body. Leptomyrmex burwelli sp. n. paratype worker. Fig. 4, front of head; Fig. 5, lateral view of body; Fig. 6, dorsal view of body.

FIGURES 19–20. Fig. 19, graph of head length versus head width. Fig. 20, graph of scape length versus head width.

FIGURES 21–22. Distribution of material examined during this study. Fig. 21, L. aitchisoni (triangle), L. burwelli (circle) and L. ramorniensis (square). Fig. 22, L. dolichoscapus (circle), L. garretti (triangle) and L. pilosus (square). Note the restricted range of most species, especially the set in Fig. 22, where all species are essentially sympatric.

FIGURES 23–24. Fig. 23, hind tibial spur of L. burwelli. Fig. 24, hind tibial spur of L. ramorniensis.