Strumigenys dagon group

Strumigenys dagon group Bolton (2000)

Worker Diagnosis
Mandibles in full-face view and at full closure subtriangular to arcuate, with a small basal gap between the mandibles and the clypeal margin; distal of the gap the mandibles engage throughout the remainder of their length. In profile dorsal margin distal of clypeus strongly down-curved, most of margin at almost a right-angle to the long axis of the head. In ventral view outer margin of mandible with a marked prebasal inflected angle. MI 8-17.

Dentition. Immediately following the basal lamella is a denticle, then 5 large teeth, the proximal 2-3 of which are slightly recurved; distally with a pair of apical denticles that share a common base, to give a total dental count of 8.

Basal lamella of mandible massively lobate, mostly or entirely concealed by clypeus when mandibles closed.

Labrum terminates in a pair of very broad blunt lobes.

Clypeus with anterior margin concave and lateral margins expanded into a lobe on each side, the maximum width across the clypeus greater than the head width across the frontal lobes. Outer margins of mandibles in full-face view intersect the anterior clypeal margin considerably mesad from the anterolateral clypeal angles. Clypeus in ventral view with lateral margins projecting well beyond the outer margins of the mandibles.

Clypeal dorsum with minute appressed hairs only, the margins without projecting hairs of any form.

Preocular carina not visible in full-face view, concealed by lateral expansion of the frontal lobe and frontal carina.

Ventrolateral margin of head in front of eye marginate, the margination weakly concave and terminating anteriorly in a triangular projection or tooth. Postbuccal impression deep, conspicuous.

Cuticle of side of head within scrobe reticulate-punctate or with upper half smooth.

Scape short, SI 57-60, subcylindrical, not markedly dorsoventrally flattened.

Leading edge of scape hairless or at most with minute appressed pubescence.

Pronotum not marginate dorsolaterally and lacking a median longitudinal carina.

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

Pilosity. Pronotal h umeri each with a fine simple to sub flagellate hair. Dorsolateral margins of head without freely laterally projecting hairs; a single pair of standing hairs on mesonotum and several pairs on waist segments and first gastral tergite.

Dorsal (outer) surfaces of middle and hind tibiae with small simple appressed hairs only.

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