Strumigenys siagodens

Identification
Bolton (2000) - Among the majority of species of this group that retain a properly shaped ventral spongiform lobe on the postpetiole it is smallest and least easily visible in siagodens. The lobe is of normal shape, with a rounded-convex ventral margin, but is very reduced in size and by no means conspicuous.

Of the two species that retain a minute vestige of the lobe Strumigenys hadrodens contrasts with siagodens  as the former has very short faint basigastral costulae, has the apical half of the first gastral tergite sculptured, has short straight hairs on the gaster, but lacks reticulate-punctate sculpture on the dorsal alitrunk and dorsal petiole node. Strumigenys appretiata is smaller than siagodens , with the pronotum virtually unsculptured and the basigastral costulae short, sparse and widely spaced.

Distribution based on Regional Taxon Lists
Neotropical Region: Paraguay.

Nomenclature

 *  siagodens. Pyramica siagodens Bolton, 2000: 163 (w.) PARAGUAY. Combination in Strumigenys: Baroni Urbani & De Andrade, 2007: 128

Worker
Holotype. TL 2.0, HL 0.59, HW 0.52, CI 88, ML 0.10, MI 17, SL 0.24, SI 46, PW 0.28, AL 0.56. Pronotal humeral hair long, fine and flagellate. Mesonotum with a single pair of long fine standing hairs that are flexuous to flagellate. First gastral tergite with long fine flexuous to flagellate hairs. Pronotal dorsum mostly glossy and with faint, quite dense longitudinal striolae that run the length of the segment but are more distinct posteriorly. Mesonotum feebly reticulate-punctate and with traces of striolate sculpture. Upper half of propodeal declivity, and dorsum of petiole node reticulate-punctate. Basigastral costulae fine, longer than dorsal length of postpetiole disc but not extending half the length of the tergite; first gastral tergite otherwise smooth and shining. Propodeal spines short, acutely triangular. Petiole node in dorsal view slightly broader than long, the lateral petiolar lobes reduced to a small dentiform prominence on each side at the posterolateral angle. Lateral spongiform lobe of postpetiole present but very reduced, retaining a short convex ventral margin but distinctly very much smaller than the lateral lobe that overhangs it.

Paratypes. TL 2.0-2.1, HL 0.56-0.60, HW 0.50-0.54, CI 86-90, ML 0.10-0.12, MI 15-17, SL 0.22-0.25, SI 46-50, PW 0.26-0.30, AL 0.54-0.59 (4 measured). No single specimen appears to show complete pilosity. In particular the fine gastral hairs seem very prone to loss by abrasion.

Type Material
Holotype worker, Paraguay: Itapua, San Rafael, 6.xi.1983, no. 82/23 (c. Dlouhy). Paratypes. 4 workers with same data as holotype.