Strumigenys pallestes

S. pallestes is one of the very few arboreal species of Strumigenys known from Africa. Numerous series have been collected from rot holes in tree trunks or branches, or from isolated workers wandering on the bark of a tree.

Identification
Bolton (1983) - In the Afrotropical region only pallestes and Strumigenys marleyi share the strange mandibular shape and odd dentition described above. The characters separating these two species are as follows:

Distribution based on Regional Taxon Lists
Afrotropical Region: Ghana, Nigeria.

Nomenclature

 *  pallestes. Strumigenys pallestes Bolton, 1971: 62, figs. 2, 3 (w.q.) GHANA. See also: Bolton, 1983: 383; Bolton, 2000: 599.

Worker
Bolton (1983) - TL 2.0-2.2, HL 0.52-0.58, HW 0.38-0.44, CI 70-77, ML 0.18-0.21, MI 32-36, SL 0.24-0.26, SI 57-62, PW 0.24-0.30, AL 0.52-0.60 (20 measured).

Mandibles in full-face view broad basally and tapering towards the apices, the inner margin with a large basal lamellate lobe whose apex is directed posteriorly and is concealed by the clypeus when the mandibles are closed. External margins of mandibles with an accentuated basal angle, the blades enclosing a central vacuity at full closure, the vacuity broadest distally and tapering towards the base. Apical fork of each mandible consisting of a pair of spiniform teeth, lacking intercalary teeth or denticles. Ventral margin of lower fork tooth with a smaller adventitious tooth arising near its base, and with a minute denticle present basally between this adventitious tooth and the lower fork tooth. Each mandibular blade with 2 preapical teeth, the proximal the longest. Eyes not visible in full-face view, concealed by the projecting upper scrobe margins. Preocular notch absent, the ventral surface of the head without a preocular groove or impression. Eyes moderate in size, with 5-6 ommatidia in the greatest diameter, their maximum diameter equal to or only fractionally less than the maximum width of the scape. Antennal scapes weakly curved basally, slightly expanded and broadest at about the midlength, their leading edges with a row of curved spoon-shaped small hairs. Dorsum of head densely clothed with short broad flattened hairs which appear scale-like to short spatulate in full-face view, the upper scrobe margins densely fringed by hairs similar in shape and size to those on the leading edges of the scapes. Dorsum of head with a transverse row of 4 short standing hairs close to the occipital margin. Head reticulate-punctate everywhere. Pronotal humeri each with a laterally projecting straight clavate hair. Lateral margins of promesonotal dorsum with a row of 4-5 clavate hairs on each side, the first 1-2 of these curve towards the midline, the remaining 3 are more or less straight. Ground-pilosity of dorsal alitrunk like that on head but the hairs sparser, frequently somewhat smaller and slightly more elevated. Metanotal groove absent. Mesonotum not depressed posteriorly, instead the promesonotum forming a single more or less evenly curved surface in profile. Propodeal teeth subtended by broad convex infradental lamellae. Sides of alitrunk uniformly reticulate-punctate everywhere. Pronotal dorsum longitudinally rugulose, usually with punctures between the rugulae. Remainder of dorsal alitrunk densely reticulate-punctate. Dorsum of petiole node weakly transversely striate, the postpetiole smooth. Spongiform appendages of pedicel segments large, the petiole ventrally with a spongiform strip which is as deep as the peduncle. Ventral spongiform lobe of post petiole distinctly larger than the exposed area of the postpetiolar disc in profile, and larger than the lateral lobe. In dorsal view the postpetiole narrow, only slightly broader than the petiole. Basigastral costulae dense, radiating on each side of a central clear area. Dorsal surfaces of petiole, postpetiole and gaster with numerous short standing hairs which are clavate apically. Colour dull yellow to brownish yellow.

Type Material
Bolton (1983) - Holotype worker, paratype workers and female, GHANA: Eastern RegIon, New Tafo, Cocoa Res. lnst. Ghana, mossy rot hole in trunk of cocoa tree, 22.vii.1970 (B. Bolton) [examined].