Strumigenys thuvida group

Strumigenys thuvida group Bolton (2000)

Species

Afrotropical-West Palaeartic

• Strumigenys belial
• Strumigenys nimravida
• Strumigenys ravidura
• Strumigenys thuvida
• Strumigenys trymala
• Strumigenys tukulta

Worker Diagnosis

Mandibles in full-face view and at full closure triangular and stoutly constructed, serially dentate and engaging throughout their lengths. In profile most or all of the dorsal margin distal of the clypeus markedly down-curved, almost at a right-angle to the long axis of the head. In ventral view the outer margin of the mandible with a prebasal inflected angle. MI 17-26.

Dentition. Following the basal lamella are 8 short but stout teeth, that may be slightly recurved; distal to these is a series of 3 denticles, giving a total dental count of 11.

Basal lamella of mandible large, a broad-based high triangle that may be broadly or narrowly rounded apically; not visible with mandibles fully closed or at most with its anterior margin just visible.

Labrum terminates in a pair of broad and broadly rounded lobes that diverge anteriorly.

Clypeus with anterior margin broad, transverse or nearly so; lateral margins of clypeus very short. Outer margins of mandibles intersect the anterior clypeal margin at the clypeal anterolateral angles.

Clypeal dorsum with minute appressed hairs, scale-like appressed hairs or elevated short hairs. Lateral margins without freely projecting hairs of any form.

Preocular carina narrow, not visible or only just visible in full-face view.

Ventrolateral border of head marginate in front of the eye, the margination terminating anteriorly in a small tooth or angle. Postbuccal impression deeply impressed and conspicuous.

Cuticle of side of head within scrobe smooth and shining, or at most weakly and superficially sculptured.

Scape short, SI 51-69, slightly dorsoventrally flattened and with a sharp leading edge that is shallowly convex throughout its length.

Leading edge of scape without projecting hairs; any pilosity present is minute, appressed and directed toward the apex of the scape.

Pronotum without a median longitudinal carina, not marginate laterally, the dorsum transversely convex.

Spongiform appendages of petiole and postpetiole well developed. Base of first gastral sternite in profile with or without a distinct pad of dense spongiform tissue.

Pilosity. Variable; pronotal humerus with or without a projecting hair, dorsolateral margins of head either with projecting hairs present, or head covered with spatulate or scale-like appressed hairs, or both. Dorsal (outer) surfaces of tibiae with short to minute closely applied pilosity only.

Sculpture. Dorsum of head behind clypeus reticulate-punctate or coarsely foveolate. Pleurae, side of propodeum and disc of postpetiole smooth and shining.

Notes

As constituted here the group contains the ravidura- and thuvida-groups of the earlier survey (Bolton, 1983).

References

• Bolton, B. 1983. The Afrotropical dacetine ants (Formicidae). Bulletin of the British Museum (Natural History). Entomology. 46:267-416.
• Bolton, B. 2000. The ant tribe Dacetini. Memoirs of the American Entomological Institute. 65:1-1028.