Strumigenys gatuda

Identification
Bolton (1983) - A very distinctive species of the emarginata-group, gatuda is characterized by its distribution of simple pilosity, reduced alitrunk sculpture and glassy smooth body.

Distribution based on Regional Taxon Lists
Afrotropical Region: Rwanda.

Nomenclature

 *  gatuda. Smithistruma gatuda Bolton, 1983: 292, fig. 11 (w.) RWANDA. Combination in Pyramica: Bolton, 1999: 1673; in Strumigenys: Baroni Urbani & De Andrade, 2007: 120. See also: Bolton, 2000: 303.

Worker
Holotype. TL 2·2, HL 0.59, HW 0.42, CI 71, ML 0.06, MI 10, SL 0.28, SI 67, PW 0.27, AL 0.60.

Mandibles with 5 relatively large teeth followed distally by two slightly smaller teeth and a series of 4 denticles before the apical tooth. Basal lamella of mandible concealed by clypeus and not visible. Anterior clypeal margin broadly and shallowly concave between the broadly rounded anterolateral angles, the margin equipped with 6 spatulate to spoon-shaped broad hairs which are strongly curved towards the midline and arranged in three pairs; the innermost pair so strongly curved together that the apices are almost touching, the outermost pair intermediate in size to the very large spoon-shaped hair at the anterolateral clypeal corner. Lateral clypeal margins shallowly convex and very feebly convergent anteriorly, equipped with a fringe of anteriorly curved large spatulate to spoon-shaped hairs. Clypeal and cephalic dorsa with a ground-pilosity of small spoon-shaped curved hairs. Sides of occipital lobes in full-face view with freely projecting long feebly clavate hairs. With head in profile the dorsum from the highest point of the vertex back to the occipital margin with a number of long erect to suberect anteriorly curved hairs which are feebly clavate to weakly remiform. Preocular laminae in full-face view weakly divergent anteriorly but reaching a maximum width before meeting the clypeus, and from there to the clypeus slightly convergent. Antennal scapes narrow basally, bent at about the basal third and broadest at about this point, the leading edge subangulate at the point of maximum width and with a series of freely projecting spatulate hairs. Flagellate hairs absent. Clypeus, area between frontal lobes and a short median strip behind that smooth and unsculptured. Remainder of head densely punctate to reticulate-punctate, the punctures and spaces between them glossy. Head in profile with vertex moderately high and narrowly rounded, the ventral surface behind the level of the eye broadly and evenly convex. Maximum diameter of eye distinctly less than maximum width of scape. Pronotum with lateral margins bluntly narrowly rounded but not marginate, the dorsum without a median longitudinal ridge or carina and the humeri lacking flagellate hairs. Anterior portion of mesonotum raised up to level of pronotal dorsum, the remainder of the mesonotum and the propodeal dorsum markedly depressed. Highest point of raised anterior portion of mesonotum with a pair of long erect stout hairs which constitute the only standing pilosity on the dorsal alitrunk. Metanotal groove absent, the mesonotal and propodeal dorsa forming a single surface. Propodeal teeth long and narrow, slightly upcurved, the infradental lamellae narrow. Alitrunk dorsum with scattered minute appressed hairs and the long mesonotal pair mentioned above. Petiole with one pair oflong straight simple hairs, postpetiole with 3-4 pairs. Gastral tergites with numerous straight hairs which are simple to feebly clavate, erect to suberect. Dorsal alitrunk glassy smooth, highly polished with widely separated small punctures. Petiole and the voluminous postpetiole glassy smooth dorsally, the first gastral tergite unsculptured except for the basigastral costulae. Pleurae of alitrunk smooth except for a patch of evenly spaced punctures occupying the central third or slightly more of the mesopleuron. Extreme base of first gastral sternite with sparse but sharply incised punctures. Spongiform appendages of pedicel segments strongly developed in profile. In dorsal view the posterior margin of the petiole node with a transverse strip which is broad and spongiform postrolaterally but which is very narrow and lamellar centrally. The concave anterior margin of the postpetiole with a narrow translucent lamellar strip, the posterior margin with a transverse strip which is broad laterally but contracted down to a narrow isthmus medially. Transverse basal strip of first gastral tergite lamellar rather than spongiform and traversed by the raised basigastral costulae. Colour light glossy brown.

Paratypes. TL 2.2-2.3, HL 0.58-0.60, HW 0.41-0.42, CI 70-71, ML 0.06, MI 10, SL 0.26-0.28, SI 63-67, PW 0.26-0.28, AL 0.60-0.62 (5 measured). As holotype.

Type Material
Holotype worker, Rwanda: Rangiro, 10.vii.1973, 1800m (P. Werner). Paratypes. 4 workers with same data as holotype; 1 worker with same data but 6.viii.1973 (MHNG; ; ).