Strumigenys tolomyla

Identification
Bolton (1983) - In the weberi-group six species are known in which the postpetiolar disc is without costulate sculpture and the metanotal groove is not impressed. These two characters are combined in Strumigenys arahana, Strumigenys fenkara, Strumigenys malaplax, Strumigenys placora, Strumigenys synkara and tolomyla . The first named is easily distinguished from the rest as it has the spongiform trip which borders the petiole node posteriorly very thick indeed, thicker than the dorsal length of the node. In the remainder this strip is quite narrow, not even approaching the length of the node. Two other species which are quickly differentiated from tolomyla ; malaplax, which lacks specialized long hairs on the cephalic dorsum similar to those on the clypeal dorsum, and placara, in which such specialized hairs are present but very much longer on the cephalic dorsum than on the clypeus. The remaining species, fenkara, synkara and tolomyla, form a close triad. S. fenkara is characterized by the conspicuously swollen nature of the specialized cephalic hairs and synkara is differentiated from tolomyla by the characters mentioned in the key and the shape of the anterior clypeal margin, which is concave in the latter species.

Distribution based on Regional Taxon Lists
Afrotropical Region: Cameroun.

Nomenclature

 *  tolomyla. Smithistruma tolomyla Bolton, 1983: 310 (w.) CAMEROUN. Combination in Pyramica: Bolton, 1999: 1673; in Strumigenys: Baroni Urbani & De Andrade, 2007: 129. See also: Bolton, 2000: 340.

Worker
Holotype. TL 2.1, HL 0.58, HW 0.39, CI 67, ML 0.06, MI 10, SL 0.27, SI 69, PW 0.27, AL 0.60.

Dentition (from paratype) of a high basal lamella followed by a small diastema, 5 relatively large teeth forming the principal row, two slightly smaller teeth, 4 minute denticles and a small apical tooth. Anterior clypeal margin evenly shallowly concave, the anterolateral angles rounded and the sides very feebly divergent posteriorly. Lateral margins of clypeus with projecting simple hairs, the shorter hairs curved anteriorly, the longer hairs projecting outwards and upcurved in their apical halves. Sides of head with numerous long fine projecting hairs. In profile the clypeal dorsum with a few upcurved hairs anteriorly and a transverse row of much longer erect sinuate hairs across the posterior clypeal margin. Ground-pilosity of cephalic dorsum behind clypeus of short fine anteriorly arched hairs whose apices are in contact or nearly in contact with the surface. Specialized pilosity of erect curved to sinuate hairs similar to those on the posterior clypeus are present on the cephalic dorsum, the longest of them no longer than those on the posterior clypeus or only very slightly longer. Scape slightly bent in basal third, the leading edge with a series of freely projecting simple hairs which are upcurved apically. Cephalic dorsum densely and coarsely reticulate-rugose, the clypeus more finely sculptured. Pronotum not marginate laterally, without a median longitudinal carina dorsally. Metanotal groove absent. Propodeal teeth fine and narrow, the infradental lamella reduced to a mere carina which follows the concavity of the declivity. Sides of pronotum and propodeum reticulate-rugose, the mesopleuron with scattered small sharply incised punctures on a smooth surface, the metapleuron mostly smooth. Promesonotal dorsum coarsely rugose, the propodeal dorsum densely punctate. Spongiform appendages of pedicel segments well developed in profile. Ventral appendage of petiole with a broad indentation in its ventral margin at about the midlength. Ventral lobe of postpetiole massive. Petiole node rugulose in dorsal view, the posterior spongiform strip narrow medially, its thickness distinctly much less than the dorsal length of the node. Postpetiole in dorsal view smooth and shining, surrounded on all sides by spongiform material. Anteriorly the postpetiole with a relatively narrow transverse spongiform strip, laterally the spongiform material increasing thickness posteriorly, the tissue thickest at the posterolateral angles. Margin of posterior spongiform appendage of postpetiole indented medially, the indentation reaching the posterior margin of the disc. Base of first gastral tergite with a dense spongiform strip, the tergite behind this level with short basigastral costulae present. Dorsal surfaces of alitrunk, petiole, postpetiole and gaster with numerous simple fine hairs. Colour brown.

Paratype. TL 2.1, HL 0.58, HW 0.38, CI 66, ML 0.05, MI 9, SL 0.26, SI 68, PW 0.26, AL 0.58. As holotype.

Type Material
Holotype worker, Cameroun: nr Yaounde, sample K2 (G. Terron). Paratype. 1 worker, Cameroun: nr Yaounde, sample FF (G. Terron).