Strumigenys ruta

Identification
Bolton (2000) - A member of the Strumigenys silvestrii-group. Isolated from the same litter sample as the holotype of Strumigenys dyseides, the two are closely related but have different forms of gastral pilosity. S. ruta also differs from dyseides by having relatively shorter mandibles, a vestigial lateral spongiform lobe on the petiole, a reticulate-punctate postpetiole disc and a pair of standing hairs on the mesonotum. However, both belong to the same small complex of species, defined and differentiated under dyseides, where ruta appears to be the closest known relative of Strumigenys skia.

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil, Colombia.

Nomenclature

 *  ruta. Strumigenys ruta Bolton, 2000: 557 (w.) COLOMBIA.

Worker
Holotype. TL 1.5, HL 0.41, HW 0.32, CI 78, ML 0.21, MI 51, SL 0.26, SI 81, PW 0.22, AL 0.40. Spiniform preapical tooth of mandible separated from apicodorsal tooth by a distance at least equal to its own length. A tiny preapical denticle present just proximal of mandibular midlength. Scape with an obtuse but conspicuous subbasal bend; curved hairs on leading edge of scape spatulate, the longest of them about equal to the maximum width of the scape. Ground pilosity of cephalic dorsum narrowly spoon-shaped; close to occipital margin is a pair of slightly more erect straighter hairs but these are quite weakly differentiated from the ground-pilosity. Apicoscrobal hair very long, fine and flagellate. Pronotal humeral hair fine and flagellate; an erect pair of fine flagellate hairs on the mesonotum. Dorsum of first gastral tergite with widely spaced flagellate hairs that are much stouter than those on the head and alitrunk; these hairs do not arise from conspicuous pits. In structure the flagellate hairs of the first tergite appear thick or flattened to ribbon-like in their basal halves; slender and simple only in their apical sections. Similar but shorter, more flattened or ribbon-like, hairs present on dorsa of petiole and postpetiole. Surface of first gastral tergite between the flagellate hairs bare, without fine simple ground pilosity. Propodeum with a pair of small teeth, subtended by narrow lamellae. Petiole in profile without spongiform tissue ventrally and without a lateral spongiform lobe; node with height of anterior face greater than length of dorsal surface (discounting posterior collar). In dorsal view petiole node broader than long. Disc of postpetiole finely superficially reticulate-punctate. Basigastral costulae about as long as postpetiole disc.

Type Material
Holotype worker, Colombia: Putumayo, Villa Garzon, 23.vii.1977 (D. Jackson).