Strumigenys tigrilla

Identification
Bolton (1983) - Rendered very distinctive by its conspicuous black and yellow colour pattern, tigrilla is also characterized by its lack of dorsal pilosity, rugulose-costulate postpetiolar dorsum, basigastral costulae which arise in a continuous row without a central clear area, and evenly sculptured dorsal alitrunk.

Distribution based on Regional Taxon Lists
Afrotropical Region: Cameroon, Gabon, Ghana, Ivory Coast.

Nomenclature

 *  tigrilla. Miccostruma tigrilla Brown, 1973a: 32, figs. 1, 2 (w.) IVORY COAST. Combination in Smithistruma: Bolton, 1983: 284; in Pyramica: Bolton, 1999: 1673; in Strumigenys: Baroni Urbani & De Andrade, 2007: 129. See also: Bolton, 2000: 306.

Worker
Bolton (1983) - TL 2.0-2.2, HL 0.56-0.62, HW 0.48-0.51, CI 82-88, ML 0.05-0.06, MI 9-11, SL 0.23-0.26, SI 48-52, PW 0.30-0.32, AL 0.55-0.62 (4 measured).

Dentition of mandibles apparently as described under mandibularis. Anterior clypeal margin very broadly and deeply arched-concave, the excavation semicircular in full-face view and the concave margin with 5 pairs of projecting scale-like to spatulate small hairs which are curved medially. Sides of clypeus weakly convergent anteriorly, equipped with a fringe of freely projecting large spatulate to spoon-shaped hairs which are curved anteriorly. Because of the width and depth of the clypeal concavity the anterolateral angles seem narrow and strongly prominent anteriorly. Dorsum of clypeus and cephalic dorsum with widely scattered decumbent to appressed anteriorly directed minute flattened hairs which are very inconspicuous; without standing hairs of any description. Antennae with 4 segments. Scape narrow basally but then the leading edge suddenly broadened into a large anteriorly prominent rounded lobe. Leading edges of scape with a row of large freely projecting spatulate to spoon-shaped hairs. Maximum diameter of eye 0.14-16 X HW. Cephalic dorsum densely and quite Sharply reticulate-punctate, the posterior clypeus similarly but more finely sculptured, the sculpture tending to fade out towards the anterior clypeal margin. Pronotal dorsum more or less flat transversely, the dorsum meeting the sides in a bluntly rounded angle. Pronotum without a median longitudinal ridge or carina. With alitrunk in profile the mesonotum forming a shallow convexity which is separate from the pronotum and propodeum. Metanotal groove extremely feebly marked by an impression, its location more obviously indicated by a change of colour. Propodeal teeth without any portion which is free of the infradentallamella. Dorsal surfaces of alitrunk, petiole, postpetiole and first gastral tergite without standing hairs of any description, only with minute appressed slightly flattened pubescence which is very sparse. Gastral tergites behind the first with weakly clavate hairs. Sides of alitrunk mostly smooth, with marginal punctation. Dorsal surfaces of alitrunk, petiole and postpetiole finely and densely reticulate-punctate to granular, the postpetiole also with fine longitudinal costulae or rugulae at least on the anterior half of the disc. Spongiform appendages of pedicel segments only moderately developed in profile, the ventral appendage of the petiole represented only by a small posteroventral lobe below the node. In dorsal view the petiole node with a narrow posterior strip and the postpetiole with an anterior strip of about the same width or even narrower. Posterior margin of postpetiole with a spongiform strip which is broadest laterally and very narrow or even interrupted medially. Posteromedian area of postpetiole disc impressed. Base of first gastral tergite with a narrow spongiform strip which is concave anteromedially. Basigastral costulae arising right across the base of the first tergite, without a broad central gap. Mandibles, clypeus and antennae yellow; remainder of head black. Pronotum, mesonotum and forelegs yellow; propodeum, pleurae, middle and hind coxae black. Middle and hind femora dusky at least basally, remainder of legs yellow. Petiole and postpetiole black. Basal third of first gastral tergite yellow or yellowish white, the rest of the gaster black.

Type Material
Bolton (1983) - Holotype worker, Ivory Coast: nr Divo, 18.iii.1963, berlesate from rain forest leaf litter (L. Brader); and paratype worker, Banco Forest Res., nr Abidjan, circuit 1, i.1963, berlesate from rain forest leaflitter (W. L. Brown) [examined].