Strumigenys adsita

A soil nesting species that has been found in rainforest and grasslands.

Identification
Bolton (2000) - The only member of the Strumigenys adsita-group. The enormously expanded keel on the petiole and the characteristic mandibular dentition make adsita one of the most easily recognized Malagasy species. These characters, coupled with the presence of spoon-shaped hairs on all dorsal surfaces and the hollow-triangular ventral spongiform lobe of the postpetiole, immediately isolate adsita from all other species.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  adsita. Strumigenys adsita Fisher, in Bolton, 2000: 624, figs. 381, 409 (w.q.) MADAGASCAR.

Worker
Holotype. TL 2.1, HL 0.48, HW 0.44, CI 91, ML 0.14, MI 29, SL 0.25, SI 58, PW 0.28, AL 0.51. With the above characters and the following. Dorsal surfaces of head, alitrunk, waist segments and gaster blanketed with spatulate to spoon-shaped ground pilosity; similar hairs fringe upper scrobe margin and leading edge of scape. Apicoscrobal and pronotal humeral hairs absent. Standing hairs absent from first gastral tergite. Cephalic dorsum, dorsum and sides of alitrunk and petiole reticulate-punctate. Promesonotum slightly convex dorsally and posteriorly bluntly dorsolaterally marginate; propodeal dorsum sloping posteriorly to the declivity. Propodeum without differentiated teeth, the propodeal lamella continuous down declivity. Peduncle of petiole in profile with a broad translucent ventral keel; spongiform tissue limited to a narrow strip along ventral margin of keel. In profile, ventral spongiform lobe of postpetiole forms a hollow triangle. First gastral tergite with basigastral costulae oblique and radiating medially on each side of a central clear area. Margin of basal truncated area of first gastral sternite with row of short, scale-like hairs.

Paraypes. TL 1.9-2.1, HL 0.46-0.49, HW 0.41-0.44, CI 86-94, ML 0.14-0.16, MI 29-35, SL 0.24-0.27, SI 56-64, PW 0.27-0.28, AL 0.49-0.56 (11 measured). As holotype.

Type Material
Holotype worker, Madagascar: grassland near Foret Ankazomivady, 28 km. SSW Ambositra, 1670 m., 20°46'30"S, 47°10'6"E, 12.i.l998, grassland, nest in soil in 2 adjoining cells, 9.5 cm. from surface, found by digging, SAM #011222 (H. G. Robertson).

Paratypes. 20 workers and 5 queens (4 alate and 1 dealate) with same data as holotype.

References based on Global Ant Biodiversity Informatics

 * Fisher B. L. 2003. Formicidae, ants. Pp. 811-819 in: Goodman, S. M.; Benstead, J. P. (eds.) 2003. The natural history of Madagascar. Chicago: University of Chicago Press, xxi + 1709 pp.
 * Fisher, B.L. and H.G. Robertson. 2002. Comparison and Origin of Forest and Grassland Ant Assemblages in the High Plateau of Madagascar (Hymenoptera: Formicidae). Biotropica 34(1):155-167.