Strumigenys rhea

Identification
Bolton (2000) - S. rhea is closely related to Strumigenys serradens and Strumigenys serraformis, relatively large species (HW 0.65 or more) from Philippines and Sulawesi. These three species share the same characteristic long low petiole node and relatively long mandibles (MI 33-36). Structurally the mandibles of the two are quite different. Those of rhea have the usual dentition of the capitata-group but have concave outer margins, whilst the mandibles of serradens and serraformis are armed with 25 or more minute denticles.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Indonesia, Sulawesi.

Nomenclature

 *  rhea. Pyramica rhea Bolton, 2000: 403, fig. 251 (w.) INDONESIA (Sulawesi). Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 126

Worker
Holotype. TL 3.4, HL 0.78, HW 0.65, CI 83, ML 0.28, MI 36, SL 0.50, SI 77, PW 0.47, AL 1.02. With the head in full-face view the middle third of the length of the outer mandibular margin is shallowly but distinctly concave. Basal lamella of mandible elongate and low, mostly visible even when the mandibles are fully closed. Seven teeth that follow the basal lamella broadly triangular, low and sharply defined. Apicoscrobal hair elongate, stout, slightly curved and pointed apically. Hairs that project from leading edge of scape very narrowly spatulate and feebly curved. Dorsum of head with a transverse row of 4 stout, apically pointed, standing hairs close to the occipital margin, and with a pair of similar hairs just in front of the highest point of the vertex. Eye with 6-7 ommatidia in the longest row. Dorsum of head reticulate-punctate with overlying fine irregular rugulae. Pronotal humeral hair stout, pointed apically. Mesonotum with a single pair of similar but blunter hairs. Dorsal surfaces of alitrunk and waist segments densely punctate to reticulate-punctate. Sides of alitrunk and waist segments mostly with the same sculpture but katepisternum and most of metapleuron smooth and shining. Propodeal teeth very short and narrowly triangular; without lamella on declivity. Petiole node in profile with a very short, sloping anterior face and a very much longer, shallowly convex dorsal surface. In dorsal view the petiole node much longer than broad. Petiole node with a single pair of standing hairs, situated close to the posterior spongiform collar. Postpetiole with two pairs of standing hairs. First gastral tergite and sternite glassy smooth except for the short basigaster costulae, the tergite with a single pair of standing hairs that straddle the midline close to the basal collar (see under paratype).

Paratype. TL 3.6, HL 0.82, HW 0.67, CI 82, ML 0.29, MI 35, SL 0.52, SI 78, PW 0.50, AL 1.06. As holotype but basal tooth of right mandible broken off. Some of the standing stout cephalic hairs are not as sharply pointed as in the holotype. Base of first gastral tergite with a transverse row of 4 standing hairs, consisting of a median pair as in the holotype and another hair on each side on the same line. It seems reasonable to assume that this was the original condition in the holotype, but that its outer hairs have been abraded away to leave just the more median pair.

Type Material
Holotype worker, Indonesia: Sulawesi Utara, Gn. Muajat, 1750 m., 25.i.1985 (M. Brendell).

Paratype. 1 worker with same data as holotype.