Strumigenys fronto

Known primarily from dry-forest litter samples, one collection was made from a soil nests.

Identification
Bolton (2000) - A member of the carisa complex in the Strumigenys arnoldi-group. S. fronto can easily be isolated by the presence of only 1 preapical tooth on left and right mandibles, a long stiff projecting filiform hair on each pronotal humerus and the dorsolateral margin of the head posteriorly with 2-3 stiff erect hairs that are longer than hairs on leading edge of scape. See Strumigenys carisa for further discussion.

Distribution based on Regional Taxon Lists
Malagasy Region: Madagascar.

Nomenclature

 *  fronto. Strumigenys fronto Fisher, in Bolton, 2000: 660, figs. 397, 419 (w.) MADAGASCAR.

Worker
Holotype. TL 3.5, HL 0.85, HW 0.73, CI 86, ML 0.46, MI 54, SL 0.56, SI 76, PW 0.39, AL 0.84. Characters of carisa-complex. Each mandible with 1 preapical tooth which is situated in the apical third; preapical tooth on left mandible usually smaller than tooth on right. Upper scrobe margin bordered by a very narrow laminar rim throughout its length, eyes partially visible in full-face view. Eye small, convex, its maximum diameter slightly greater than maximum width of scape. Eye located slightly inwards from margin and apex formed by the junction of the posterior preocular notch and ventral scrobe margin. Scape more or less subcylindrical, basal portion slightly expanded and approximately straight; hairs on leading edge narrowly spatulate. Cephalic dorsum densely clothed with curved narrowly spatulate ground-pilosity; upper scrobe margin fringed with hairs that are similar in size and shape to those on the dorsum. Cephalic dorsum with 7 pairs of long stout standing remiform hairs arranged as follows: transverse row of 3 pairs close to the occipital margin; dorsolateral margin posteriorly with 3 pairs of hairs that are longer than hairs on leading edge of scape; 1 pair on vertex. Pronotal humeral hair long and stout, filiform and projecting; humeral angles rounded. Mesonotum with 1 pair of stout standing narrowly spatulate hairs on anterior margin. Propodeum with two pairs of short, posteriorly curved hairs immediately anterior of propodeal spines. Ground-pilosity on alitrunk dorsum as on head but sparser. Dorsum of alitrunk in outline convex anteriorly, posterior alitrunk gradually sloping down to declivity, anterior propodeum slightly raised above posterior mesonotum. Metanotal groove represented by a shallow impression. Propodeal spines narrowly triangular, margins spongiform; propodeal lamella absent. Alitrunk dorsum and sides of pronotum densely reticulate-punctate. Pleurae mostly reticulate-punctate, katepisternum and central portion of metapleuron partially smooth. Petiole node in dorsal view approximately as long as broad. Postpetiole disc reticulate-punctate. In profile ventral spongiform tissue of petiolar peduncle a narrow, irregular strip that is continuous along the base of the peduncle, maximum depth of strip slightly less than the maximum width of eye. Ventral spongiform tissue of postpetiole moderately developed. Basigastral costulae short, distinct and widely spaced. Dorsal surface of petiole, postpetiole, and gaster with stout standing remiform to narrowly spatulate hairs. Colour medium brown.

Paratypes. TL 3.3-3.7, HL 0.80-0.88, HW 0.68-0.76, CI 85-90, ML 0.44-0.49, MI 52-57, SL 0.53-0.56, SI 73-78, PW 0.37-0.41, AL 0.76-0.86 (8 measured). As holotype.

Type Material
Holotype worker, Madagascar: Causse de Kelifely, 20-30.xi.1974, forest humus and litter, dry forest (A. Peyrieras).

Paratypes. 9 workers with same data as holotype.

References based on Global Ant Biodiversity Informatics

 * Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
 * 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.