Strumigenys flavianae, Chaul, 2023

Chaul, Júlio Cezar Mário, 2023, A New Ant Species of Strumigenys Smith, 1860 (Hymenoptera: Formicidae) from the Brazilian Atlantic Forest, Taxonomy (Basel, Switzerland) 3 (2), pp. 221-231 : 224

The flavianae -group

(i) Mandible small in relation to head, multidentate ( Figure 1 A), likely performing the gripping mechanism of action [ 8]. (ii) Mandible inner margin (masticatory) with a small, triangular basal lamella, followed, without diastemmic gap, by a series of six–seven sharp teeth, then four–five truncate teeth and a sharp apical tooth ( Figure 2 B). (iii) Mandible’s outer margin confluent with clypeal lateral margin ( Figure 1 A). (iv) Labrum with basolateral expansions, followed by mildly convex lateral margins that form a pair of relatively low, robust lobes; lobes with up to four flagellate chaetae that are approximately two-thirds of labrum length, some flattened and some simple ( Figure 2 G). (v) Head much longer than wide ( CI 51) ( Figure 1 A); mesosoma, petiole and legs also elongate ( Figure 1 B, D). (vi) Flagellate, subflagellate and wire-like setae distributed on body in an apparently untidy manner; however, the apicoscrobal, humeral and mesonotal pairs stand out as larger, wire-like setae ( Figure 1). (vii) Freely projecting, wire-like setae on scape anterior margin, not inclined in a defined direction ( Figure 2 C). (viii) Dorsum of mesosoma discontinuous, promesonum much higher than propodeal level. (ix) Triangular cuticular lamella on anterolateral edge of mesonotum, directly over the mesonotal spiracles (best seen in ventrolateral view, Figure 2 F). (x) Mesopleura excavation inconspicuous, but clearly discernible in specimens with dissected forecoxa, excavation filled with whitish setae. (xi) Propodeal spine long, propodeal lamella reduced. (xii) Femoral and tibial glands visible in all legs, small; some tarsomeres with glands visible as well (see description below). (xiii) Petiole node in profile long and low. (xiv) Well-developed spongiform tissue on the waist segments ( Figure 1 B, C). (xv) Basigastral costulae well-marked, smaller than postpetiole disc length ( Figure 1 C).