Leptomyrmex varians

L. varians has been recorded in dry sclerophyll and Eucalyptus, Casuarina, Melaleuca and Callitris open forests. Nests occur as large or small craters in soil, in the open, or at the base of live trees.

Identification
L. varians is a distinctly slender and elongate species that occurs in southeastern to central Queensland, from approximately Brisbane to Mackay, in a broad arc that sweeps inland. This species tolerates drier habitat than most other species in the genus. Coloration is usually pale orange with contrasting black legs, including coxae but excluding tarsi, and dark brown antennal scapes and tips. This species may be confused with two other pale-bodied congeners with which it is sympatric in southeast Queensland, Leptomyrmex cnemidatus and Leptomyrmex rufipes. Distinguishing L. varians from these species are the entirely dark coxae, femora and tibiae; in Leptomyrmex cnemidatus the coxae and proximal portion of femora are pale and in L. rufipes the tibiae are pale. Furthermore, the narrowed, but not constricted or projecting posterior margin of the head in L. varians is unlike that in L. cnemidatus (broadly rounded) or L. rufipes (constricted and projecting).

Key to Australian Leptomyrmex Species

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Castes
Queens have yet to be collected.

Nomenclature

 *  varians. Leptomyrmex varians Emery, 1895g: 352, fig. 3 (w.) AUSTRALIA. Senior synonym of angusticeps, decipiens: Lucky & Ward, 2010: 58. See also: Wheeler, W.M. 1934c: 101.
 * decipiens. Leptomyrmex erythrocephalus var. decipiens Wheeler, W.M. 1915d: 268 (w.) AUSTRALIA. Wheeler, W.M. 1934c: 90 (m.). Subspecies of erythrocephalus: Wheeler, W.M. 1934c: 90. Junior synonym of varianss: Lucky & Ward, 2010: 58.
 * angusticeps. Leptomyrmex varians st. angusticeps Santschi, 1929f: 93, fig. 3 (m.) AUSTRALIA. Junior synonym of varians: Lucky & Ward, 2010: 58.

Worker
Lucky and Ward (2010) - HL 1.92–2.18, HW 1.04–1.19, MFC 0.22–0.28, IOD 0.61–0.70, SL 3.89–4.28, EL 0.36–0.43, WL 3.78–4.29, PW 1.01–1.18, DPW 0.37–0.52, HTL 4.77–5.53, HTWmin 0.13–0.16, HTWmax 0.20–0.31, CI 0.53–0.59, SI 3.31–3.82, OI 0.10–0.15, HTC 0.44–0.64.

Medium sized species (HL 1.92–2.18; HW 1.04–1.19) with a distinctly narrow head (CI 0.53–0.59) excluding mandibles, nearly twice as long as broad. Head widest at eyes, sides of head nearly straight and parallel, posterior to eyes narrowing with straight sides toward posterior margin, forming a slightly constricted ‘neck’. Masticatory margin of mandible with approximately 25 small teeth mostly of uniform size, with larger teeth confined to anterior half. Anterior clypeal margin weakly convex. Eyes positioned approximately at midline of head, small, convex, hairless, surpassing margins of head. Antennal scapes very slender and terete, extending beyond posterior margin by nearly 2/3 of their length.

Pronotum slightly more than 1.5 times as long as broad. Declivity of propodeum very convex, about half the length of the dorsal face, which is flat to weakly concave in profile. Petiolar node triangular in profile with faint longitudinal impression on dorsal face of petiole. Posterior face of petiole longer than anterior face, angle rounded, ventral surface concave. Gaster narrow, elliptical. Legs very slender, tibiae mildly compressed.

Surface subopaque, very finely shagreened. Mandibles with a row of coarse punctures along apical border. Pubescence whitish, extremely short and fine hairs on mandibles and clypeus feebly developed. Long, coarse black hairs on venter sparse. Generally, head, thorax and antennae rufotestaceous, with antennal scapes and tips of mandibles dark brown, and with legs, including coxae, black. Tarsi yellow. Gaster, pronotum and sometimes a spot on the mesonotum black. Some series, however, are brownish-black, with a slight bluish sheen, and only the antennae, tarsi and anterior third of head are lighter (e.g. specimens from Isla Gorge NP, 50km N Taroom and White Mountains NP).

Male
Lucky and Ward (2010) – measurements (n = 4) HL 1.53–1.58, HW 1.12–1.16, SL 0.34–0.37, EL 0.55–0.61, HTL 4.22–4.71, CI 0.72–0.75, SI 0.30–0.32, SI2 1.01–1.11.