Strumigenys urrhobia

Identification
Bolton (2000) - A member of the Strumigenys schulzi-group. The material examined from Brazil (a single specimen in MZSP) has the eyes with 4 ommatidia in the longest row and lacks a conspicuously projecting apicoscrobal hair. The eyes are only slightly larger than the Trinidad and Colombia samples where the longest row has 3 ommatidia. This is not considered significant as many species show variation in eye size of this magnitude. Lack of the apicoscrobal hair is of greater significance as location and number of specialised hairs is usually consistent within species, but because only a single specimen is present it is impossible to say whether its absence is natural or the result of abrasion.

S. urrhobia shares a diagnostic dental pattern with Strumigenys emiliae, described in detail under the introductory notes on the species-group. In both species the three stout basal teeth and the broad plate-like fourth tooth tend to be conspicuous, even when the mandibles are fully closed. Both species also have relatively small eyes, slender scapes, convex anterior clypeal margins and postpetiole discs that are not blanketed with dense reticulate-punctate sculpture. The two are easily separated as urrhobia has erect hairs on the vertex and at the pronotal humeri; absent from both these locations in emiliae.

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil, Colombia, Ecuador, Trinidad and Tobago.

Nomenclature

 *  urrhobia. Pyramica urrhobia Bolton, 2000: 228, figs. 154, 193 (w.) TRINIDAD. Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 130

Worker
Holotype. TL 1.7, HL 0.44, HW 0.36, CI 82, ML 0.10, MI 23, SL 0.22, SI 61, PW 0.22, AL 0.46. Dentition as described under notes on group. Anterior clypeal margin convex; outer margins of fully closed mandibles passing outside anterolateral clypeal angles in full-face view. Scape slender, in dorsal view not strongly dorsoventrally flattened, broadest distal of the midlength. Eye relatively small, with 3 ommatidia in the longest row. Apicoscrobal hair stout and distinct, slightly thickened apically and weakly curved anteriorly. Cephalic dorsum with a transverse row of 4 long erect hairs behind highest point of vertex, these hairs strongly differentiated from the ground-pilosity which is of small curved narrowly spatulate hairs that are subreclinate. Pronotal humeral hair stout and straight; mesonotum with a single pair of similar standing hairs. Waist segments and first gastral tergite with stout erect hairs that tend to be somewhat thickened apically and curved posteriorly. Dorsal and lateral surfaces of ali trunk reticulate-punctate except for a smooth area on the katepisternum. Ventral surface of petiole with a cuticular carina but lacking a spongiform curtain. Petiole node in dorsal view broader than long, feebly reticulate-punctate. Disc of post petiole superficially sculptured, weakly granulate, not smooth but not reticulate-punctate. Basigastral costulae sharply defined, remainder of tergite smooth.

Paratypes. TL 1.7-1.8, HL 0.44-0.46, HW 0.36-0.38, CI 80-84, ML 0.10-0.11, MI 22-24, SL 0.2-0.24, SI 60-63, PW 0.22-0.26, AL 0.46-0.48 (6 measured).

Type Material
Holotype worker, Trinidad: Mayaro, 5.viii.1976 (J. Noyes).

Paratypes. 2 workers Trinidad: Arena Res., 3.viii.1976 (J. Noyes); 2 workers Trinidad: Brasso, 28.vii.1976 (J. Noyes); 4 workers Colombia: Putumayo, Villa Garzon, 14.viii.1977 (D. Jackson).