Stictoponera binghamii

This species has the largest distribution range of any Gnamptogenys species.

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Identification
Lattke (2004) - Head subquadrate in frontal view, lateral margins broadly convex and subparallel, anterior margin of clypeal lamella with anteromedian lobe convex to bluntly pointed; occipital lobes small or obsolescent. Mesosoma with broadly convex dorsal margins in lateral view, declivitous margin concave; petiolar node with evenly convex dorsal margin in lateral view; ventral petiolar process subquadrate to triangular with posterior angle. Also see the nomenclature section below.

Distribution
Lattke (2004) - G. binghamii is the most widely distributed species, found from India to Papua New Guinea, as well as in the Philippines.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Borneo, Indonesia, Malaysia, New Guinea, Philippines. Oriental Region: India, Myanmar, Thailand, Vietnam. Palaearctic Region: China.

Habitat
Lattke (2004) - Habitat labels indicate that G. binghamii mostly inhabits mesic forested areas, from lowlands to about 1500m, including dipterocarp-mixed forests and pine-oak forest in northern Thailand.

Nomenclature

 *  binghamii. Ectatomma (Stictoponera) binghamii Forel, 1900d: 317 (w.) MYANMAR. Viehmeyer, 1916a: 112 (q.m.); Wheeler, G.C. & Wheeler, J. 1976a: 43 (l.); Imai, Brown, et al. 1984: 67 (k.). Combination in Stictoponera: Emery, 1911d: 47; in Gnamptogenys: Brown, 1958g: 227. Senior synonym of borneensis: Brown, 1954h: 5. See also: Lattke, 2004: 86.
 * borneensis. Stictoponera borneensis Emery, 1900d: 662 (footnote) (w.) BORNEO. Junior synonym of binghamii: Brown, 1954h: 5.

Lattke (2004) - Most specimens studied fall into two allopatric morphotypes. Larger specimens have abundant strigulae on the scapes, a convex anteromedian clypeal margin, propodeal denticles with parallel sides, slightly arched and basally bent metacoxal teeth, and smooth cuticle on the dorsoposterior margin of the fourth abdominal tergite. They are found from western Malaysia to Borneo and into the Philippines. Smaller forms bear more resemblance to the syntypes of G. binghamii (especially those from Kottiyor, India, [MCZC]) and tend to have less strigulate scapes, a narrow posterior band of striae on the fourth abdominal tergite, triangular propodeal denticles, straight metacoxal teeth, and the clypeal lamella produced anteromedially as a blunt denticle or angle. This smaller form is found from India to Thailand, with a single specimen recorded from Borneo. The large eastern forms have smaller eyes than the smaller-bodied western populations. Besides these two morphotypes, there are a few specimens from Thailand representing intermediate forms and a nest series of small forms from Borneo with a smooth posterior margin on the fourth abdominal dorsum, strigulose scapes, and a clypeal lamella with an anteromedian point. Specimens from the Philippines and New Guinea have a larger degree of smooth cuticle on the petiolar node and propodeal dorsum, including the fourth abdominal sternite. They may also have a triangular subpetiolar process without a posterior angle.

The illustration of G. binghamii in Tang et al. (1995:28) is not G. binghamii but could be a member of the taivanensis group based on the compressed petiolar node. Gnamptogenys crassicornis (of the coxalis group) could be confused with G. binghamii, but G. crassicornis has smaller eyes, a more flattened petiolar dorsum when seen laterally, strigulae on most of the fourth abdominal tergite in lateral view, and antennal segments 3-4 longer than wide. In G. binghamii the fourth abdominal tergite when seen dorsally in full-length view has evenly convex lateral margins that gradually converge with each other posterad; in G. crassicornis the tergite is roughly funnel shaped with the anterolateral margins abruptly converging for a short distance before gradually converging posterad. Wheeler and Wheeler (1976:43) described larvae of G. binghamii from Sulawesi and Imai et al. (1984) described the karyotype. Viehmeyer (1916:112) described the queen and male of G. binghamii, though the male probably represents a different species. A single male from Singapore (H. Overbeck leg) in the [MHNG] is labeled as a cotype of Stictoponera binghamii, yet Forel (1900) described the species from workers only. This male has abundant rugosities on the postpetiolar tergite, fine strigulae on the fourth abdominal tergite, and a triangular subpetiolar process, all characters that are not found on workers associated with G. binghamii males.

Worker
Lattke (2004) - Metrics (n = 22): HL 1.05-1.35, HW 0.86-1.07, ML 0.54-0.65, SL 0.78-1.11, ED 0.16-0.26, WL 1.39-1.78 mm. CI 0.76-0.88, SI 0.88-1.05, MI 0.55-0.65, OI 0.17-0.28. Head subquadrate in frontal view, lateral margins broadly convex and subparallel, anterior margin of clypeal lamella with anteromedian convex to bluntly pointed lobe; frons rugulose-punctate with fine striae on transverse arcs between punctae; clypeus longitudinally strigulose, with strigulae partially extending onto lamella; scape varies from mostly smooth to mostly strigulose; occipital lobes small, occipital lamella well developed, convex to slightly angular at ends.

Mesosoma with broadly convex dorsal margin in lateral view; pronotum with lamellate humeral angle; mesosomal dorsum foveolate with longitudinal median smooth area extending from posterior pronotum to mesonotum; propodeal dorsum densely foveolate, side mostly foveolate, propodeal declivity concave to convex in lateral view, propodeal declivity mostly smooth; propodeal denticles low, triangular or subcylindrical. Dorsal margin of petiolar node usually evenly convex in lateral view, dorsal margin varies from dome shaped to slightly flattened dorsally; dorsum usually densely foveolate; ventral process subquadrate to triangular, usually with posterior angle; postpetiolar dorsum punctate or foveolate, with posterior band of narrow strigulae; sternum with transverse strigulae; dorsum of abdominal segment 4 mostly smooth with scattered punctulae or punctae, depressions denser and deeper on sides, small strigulose area occasionally present on anterolateral corner, sternum strigulose. Fore coxa mostly smooth anterad in lateral view and transversely strigulose posterad; fore tarsus opposite strigil with single seta followed apically by row of slenderer setae; metacoxal tooth relatively straight. Dorsum of thorax and abdominal segments 1-4 with scattered erect to subdecumbent hairs. Body color ranging from dark brown to ferruginous; mandibles, antennae, legs lighter colored.

Queen
Lattke (2004) - Metrics (n = 1): HL 1.46, HW 1.13, ML 0.75, SL 1.20, ED 0.28, WL 2.07 mm. CI 0.77, SI 1.06, MI 0.66, OI 0.25. Pronotum foveolate; mesopleuron foveolate with low longitudinal striae; mesonotum with scattered punctae and low longitudinal undulations, propodeal dorsum densely foveolate.

Male
Lattke (2004) - Metrics (n = 1): HL 0.93, HW 0.82, ML 0.52, SL 0.30, ED 0.33, WL 1.73 mm. CI 0.88, SI 0.37, MI 0.63, OI 0.40. Frons strigulose, becoming irregularly areolate laterally; with longitudinal crest extending from posterior margin of clypeus to anterior margin of median ocellus, clypeus mostly smooth with few longitudinal strigulae, anterior margin of clypeal lamella forming blunt obtuse angle. Pronotum foveolate; mesonotum mostly smooth with few scattered foveolae; mesopleuron mostly smooth with scattered foveolae; metapleuron mostly rugulose; propodeal dorsum areolate-rugulose. Postpetiole mostly smooth with scattered foveolae and low longitudinal strigulae; fourth abdominal tergite smooth.

Type Material
Lattke (2004) - Syntype workers: Burma [Myanmar] (Bingham) (MHNG) [Examined].

Stictoponera borneensis Emery, 1900b:662. Holotype worker by monotypy: Sarawak(MCSN) [Not examined]. Synonymy by Brown, 1954b:5.