Strumigenys oxysma group

Strumigenys oxysma group Bolton (2000)

Worker Diagnosis
Mandibles in full-face view and at full closure triangular, with serially dentate masticatory margins that engage throughout their visible length. In ventral view outer margin of mandible without a prebasal inflected angle. MI 11-22.

Dentition. Basal dental row of 7 relatively low triangular teeth that follow the basal lamella without a diastema. Distal of the 7 teeth are 4 minute denticles and a small apical tooth, giving a total dental count of 12.

Basal lamella of mandible a n elongate low lobe, not or partially visible when mandibles closed.

Labrum terminates in a pair of digitate to conical narrow lobes.

Clypeus with anterior margin prominent and narrowly rounded; in full-face view the sides evenly converging anteriorly, more or less continuing a line with the outer margins of the closed mandibles.

Clypeal anterior margin and dorsum with weakly clavate to remiform hairs that curve posteriorly or posteromedially; anteriormost one or two pairs usually project laterally in full-face view and curve posteriorly. Clypeal margins without a continuous fringe of anteriorly curved spatulate to spoon-shaped hairs.

Preocular carina conspicuous in full-face view.

Ventrolateral margin of head between eye and mandible angular but not sharply demarcated. Postbuccal impression small and shallow.

Cuticle of side of head within scrobe densely reticulate-punctate.

Scape moderate, SI 68-83, cylindrical to subcylindrical, the dorsum and ventre not converging anteriorly to form a flange or thin lamella that constitutes the leading edge. Ventral surface of scape convex to shallowly concave.

Leading edge of scape with all hairs simple to narrowly spatulate, all curved or inclined toward the scape apex.

Pronotal dorsum with a median longitudinal carina that often extends onto the mesonotum.

Propodeum bidentate; lamella present on declivity, no projecting propodea1 lobes at base of declivity.

Spongiform appendages of waist segments strongly developed; subpetiolar spongiform strip deeper than thickness of peduncle in profile. Base of first gastral sternite in profile without a pad of spongiform tissue.

Pilosity. Pronotal humeral hair flagellate. Dorsal alitrunk, petiole, postpetiole and first gastral tergite with fine, simple to flagellate hairs; no clavate, remiform or other bizarre setae present; flagellate hairs usually present projecting from dorsolateral margins of head in full-face view. Ground-pilosity of head of small, curved fine to narrowly spatulate hairs.

Sculpture. Dorsum of head behind clypeus reticulate-punctate to finely reticulate-rugulose.

Dorsal alitrunk mostly shining, with sculptural vestiges usual on pronotum; pleurae, propodeum, disc of postpetiole and first gastral tergite smooth.