Strumigenys spathoda

One of the few non-type collections of this ant was from a rainforest litter-sample.

Identification
A member of the arnoldi complex in the Strumigenys arnoldi-group.

Bolton (1983) - This distinctive species has the shortest mandibles yet recorded for a member of Strumigenys in the Afrotropical region. It is related to Strumigenys tetraphanes but does not possess the massively lobate expansions of the anterior scape margins seen in that species and has pronotal flagellate hairs present.

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

Nomenclature

 *  spathoda. Strumigenys spathoda Bolton, 1983: 393, fig. 62 (w.) TOGO. See also: Bolton, 2000: 596.

Worker
Holotype. TL 2.1, HL 0.55, HW 0.44, C1 80, ML 0.16, MI 29, SL 0.27, SI 61, PW 0.27, AL 0.56.

Mandibles very short, stout and powerfully constructed, their outer margins convex. Apical fork of each mandible with 2 spiniform teeth, the upper of which is very long, its length distinctly greater than 0- 5 x ML; apical forks without intercalary teeth or denticles. Each mandible with 2 pre apical teeth, the proximal by far the longest (just less than 0·5xML) and situated at or just distal of the midlength of the blade. Distal preapical tooth less than half the length of the proximal. Upper scrobe margins bordered by a narrow rim or flange whose free margins are irregular, the eyes not visible in full-face view. Eyes very small, their maximum diameter conspicuously very much less than the maximum width of the scape. Preocular notch absent, the ventral surface of the head without a preocular transverse groove or impression on each side. Antennal scapes flattened and expanded, the leading edge broadly convex and prominent, equipped with a row of large spoon-shaped hairs which are about equal in size to those bordering the upper scrobe margins. Dorsum of head from the posterior clypeal margin to about the midlength densely clothed with broad anteriorly curved spoon-shaped hairs which appear scale-like in full-face view. Hairs of the same shape and size fringe the upper scrobe margins. Behind the midlength of the head the hairs are distinctly much smaller and narrow, and contrast strongly with those on the anterior half. Dorsum of head with a transverse row of 4 short stout standing hairs close to the occipital margin, without a more anteriorly situated pair. Cephalic dorsum reticulate-punctate to granular. Pronotal humeri each with a fine flagellate hair (apparently easily lost by abrasion in this species). Mesonotum with a single pair of standing hairs. Ground-pilosity of dorsal alitrunk consisting of sparse small hairs similar to those on the posterior half of the head. Metanotal groove represented by a short line on the dorsum, very feebly impressed in profile. Mesonotum not sharply depressed behind the level of the pair of hairs, instead its surface forming a fairly even slope. Propodeal teeth triangular and subtended by broad infradental lamellae. Sides of pronotum superficially sculptured, the pleurae and sides of prop ode urn mostly smooth, with some faint peripheral punctation. Pronotal dorsum sparsely longitudinally rugulose, the remainder of the dorsal alitrunk reticulate-punctate. Dorsum of petiole node punctate, the postpetiole smooth (when clean, in the holotype the surface is obscured by a thin layer of wax or dirt). Spongiform appendages of pedicel segments well developed. Petiole with a broad ventral strip which at its broadest is equal to the depth of the peduncle. Ventral and lateral spongiform lobes of post petiole subequal, the former marginally larger and about the same size as the exposed area of the postpetiolar disc in profile. Basigastral costulae short but quite sharply defined. Dorsal surfaces of petiole, postpetiole and gaster with stout standing hairs which are thickened to clavate apically. Colour medium brown.

Paratypes. TL 2.0-2.1, HL 0.53-0.55, HW 0.41-0.44, CI 77-81, ML 0.14-0.16, MI 26-30, SL 0.24-0.26, SI 55-61, PW 0.25-0.28, AL 0.48-0.56 (5 measured).

As holotype. All members of the type-series are covered to some extent by a thin layer of dirt or a waxy deposit which obscures some features. In particular the sculpture of the dorsal body is difficult to discern and the layer tends to obscure the pilosity.

Type Material
Holotype worker, Togo: Palime, Klouto Forest, 20-25.iv.1974 (Vit). Paratypes. 5 workers with same data as holotype (MHNG; ; ).

References based on Global Ant Biodiversity Informatics

 * Belshaw R., and B. Bolton. 1994. A survey of the leaf litter ant fauna in Ghana, West Africa (Hymenoptera: Formicidae). Journal of Hymenoptera Research 3: 5-16.
 * Bolton B. 1983. The Afrotropical dacetine ants (Formicidae). Bulletin of the British Museum (Natural History). Entomology 46: 267-416.
 * Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65