Leptomyrmex rufipes

L. rufipes has been recorded in rainforest, mesophyll vine forest, Eucalyptus open forest, and wet and dry sclerophyll. Nests occur in cavities in live trees, on the ground at tree bases, in large open mounds, in or under logs, and under rocks.

Identification
Workers are slender and long-limbed. The black gaster and (usually) dark distal portions of the femora contrast with the otherwise pale orange head, mesosoma and appendages. In body size and coloration, this species resembles Leptomyrmex cnemidatus and Leptomyrmex varians. The pale tibiae of L. rufipes easily distinguish it from the others, which have dark tibiae. The necklike constriction at the posterior margin of the head is also distinctive - this margin is broadly rounded in L. cnemidatus. In L. varians the head narrows beyond the eyes, but does not project into a dorsoventrally compressed ‘neck’. Head shape is sufficient to distinguish L. rufipes from all congeners with the exception of its sister species, Leptomyrmex ruficeps and Leptomyrmex rothneyi. These species can be separated from L. rufipes based on color patterns and geographic range: L. ruficeps is black with a red head and restricted to the Wet Tropics and L. rothneyi is a mottled, dark species confined to the southeast corner of Queensland. (Lucky and Ward 2010)

Key to Australian Leptomyrmex Species

Distribution
This species occupies the widest geographic range of all the Leptomyrmex species, extending from the base of the Cape York Peninsula in north Queensland to the northern border of New South Wales. (Lucky and Ward 2010)

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Nomenclature

 *  rufipes. Leptomyrmex varians var. rufipes Emery, 1895g: 352 (w.) AUSTRALIA. Lucky & Ward, 2010: 52 (ergatoid q., m.). Subspecies of varians: Wheeler, W.M. 1934c: 104. Raised to species: Lucky & Ward, 2010: 50. Senior synonym of quadricolor: Lucky & Ward, 2010: 50.
 * quadricolor. Leptomyrmex varians subsp. quadricolor Wheeler, W.M. 1934c: 104 (w.) AUSTRALIA. Junior synonym of rufipes: Lucky & Ward, 2010: 50.

Worker
Lucky and Ward (2010) – measurements (n = 11) HL 1.94 –2.43, HW 1.08–1.39, MFC 0.24–0.34, IOD 0.59–0.78, SL 3.62–4.35, EL 0.40–0.46, WL 3.61–4.52, PW 0.96–1.26, DPW 0.37–0.51, HTL 4.52–5.67, HTWmin 0.14–0.19, HTWmax 0.16–0.25, CI 0.54–0.64, SI 2.75–3.35, OI 0.11–0.13, HTC 0.61–0.88.

Medium sized species (HL 1.94 –2.43, HW 1.08–1.39) with head long and slender, excluding mandibles head less than twice as long as broad (CI 0.54–0.64). Head widest at eye level, sides of head subparallel, narrowing anteriorly, genae slightly concave. Posterior to eyes, head narrowing abruptly to dorsoventrally flattened neck-like constriction. Masticatory margin of mandible with 15 to 20 teeth and denticles interspersed. Anterior clypeal margin flat to weakly concave. Eyes positioned approximately at midline of head, eyes small, convex, hairless, not reaching lateral margins. Antennae long and slender, not compressed, scapes surpassing posterior margin of head by 2/3 their length.

Pronotum slender, elongate. Propodeum short, dorsal face of propodeum flat or with transverse impression at anterior end, declivitous face short and convex, propodeal angle very rounded. Petiole triangular in profile, posterior face with slight median longitudinal impression, dorsum rounded, posterior face longer than anterior face. Ventral surface of petiole nearly flat. Gaster elongate-elliptical. Legs very long and slender, not compressed.

Surface very finely shagreened and somewhat shining throughout. Mandibles with a coarse row of punctures along margin. Pubescence pale, sparse. Hairs minimal, confined to clypeus, venter and gaster, 0–5 brown bristles on hind tibiae. Body rufotestaceous with black gaster. Head and antennae rufotestaceous. Femora pale at base and sometimes throughout, but often the distal 1/4 to 3/4 of the femur is black. Tibiae and tarsi yellow, gaster black with the anterior portion of first segment and anal orifice pale yellow.

Queen
Lucky and Ward (2010) – Head broader than in worker. Three ocelli deeply set into head in triangular formation, the anteriormost one largest, the posterior two smaller. Pronotum, mesonotum and propodeum more voluminous than in worker. Dorsal face of propodeum convex, lacking transverse impression. Petiole broader than high, with flat dorsal face. Gaster globose, larger than in worker. Scapes, femora and tibiae robust.

Queen coloration similar to that of worker, but with only the first one or two segments of the gaster black, and the remainder rufotestaceous.

Male
Lucky and Ward (2010) - measurements (n = 11) HL 1.57–1.92, HW 1.14–1.37, SL 0.38–0.50, EL 0.59–0.71, HTL 4.61–4.95, CI 0.68–0.77, SI 0.33–0.37, SI2 0.65–0.78.