Fernández, F., 2003:
Worker measurements. Holotype (Paratypes, n=13). HL 0.97 (0.90-0.93) HW 0.89 (0.85- 0.89) SL 0.61 (0.54-0.61) EL 0.09 (0.08-0.09) WL 0.96 (0.90-0.97) GL 1.13 (1.06-1.15) TL 3.99 (3.64-3.88) CI 90 (91-98) SI 69 (60-68).
Worker diagnosis. Mandibles with 6 teeth decreasing in size from the apical teeth. Eyes with 22 to 30 facets. Hypostomal tooth broad, low, with rounded apex. Promesonotum convex, metanotal groove distinct. Propodeum sloping with two short spines directed upward, outward and backward. Petiole high, campaniform with anterior side sloping and posterior side more or less convex. Postpetiole high, campaniform, and with posterior face concave. Head and promesonotum coarsely reticulate-rugulose with longitudinal trend in head dorsum and central area of promesonotum dorsum. Propodeal dorsum irregularly rugulated. Space between propodeal spines with curved transverse rugulae. Hairs blackish to dark brown. Body black, sides of mesosoma and petiole dark brown. Gaster, legs and antennae light brown.
Queen measurements. HL 0.98-0.99 HW 0.92-0.94 SL 0.56-0.59 EL 0.19-0.20 WL 1.11-1.13 GL 1.23-1.24 TL 4.24-4.26 CI 92-94 SI 60-64.
Differing from workers in the normal myrmicine queen traits (Fig. 42). Three ocelli present, the anterior in fossae. Eyes with more than 120 facets. Wings as in Fig. 43, large (front wing 3.85 mm long). Wings densely and finely hairy.
Male measurements. HL 0.57 HW (including eyes) 0.65 SL 0.52 EL 0.25 WL 0.95 GL 1.1 TL 3.31 CI 114 SI 80.
Male (undescribed, Figs. 43-44). With the general traits of myrmicine male. Head hemispheric with prominent and globose eyes. Mandibles simple, pointed. Palpal formula (in situ) 2,2. Clypeus medially protuberant, convex. Frontal carinae covering covering only partially antennal receptacles. Eyes with numerous facets (>30 in maximun diameter line). Three prominent spherical ocelli. Scape less curved than in workers, surpassing conspicuously vertexal border. Antennae 13-segmented, flagellomeres increasing in size from scape to apex, without evident club. Propodeal spiracle posterad and laterad. Propodeum without spines. Wings densely hairy, but less than in females. Petiole subcampaniform, with the node evenly meeting in a rounded summit, postpetiole dome-shaped, devoid of ventral transverse carinae. Promesonotum, major areas of sides of thorax and gaster smooth and shining, promesonotum with several punctures. Head, mesonotum, propodeum lateral and dorsal, petiole and postpetiole irregularly rugulated, in anterior head border with transverse trend, as well as propodeal, petiolar and postpetiolar dorsum. Body heavily hairy. Head, mesosomal dorsum, petiole, postpetiole and gaster with conspicuous suberect long hairs, those of petiole and postpetiole more dense and reclined. Antennae heavily covered with short decumbent hairs. In full face view, several long hairs produced outward and forward from clypeal area. Mandibles with long curved hairs produced outward and forward. Numerous short, erect hairs on eyes.
Comments. A. vaderi is one of the largest species in the genus. It can be separated from other species (especially from the closely-related A. myops ) by body size, eye size, mesosomal sculpture and postpetiole shape, and from A. grandis by mesosomal profile, sculpture, and size.
This is the first description of a queen for Neotropical species, and the first world description of a male.
The dark aspect of these ants evokes Darth Vader, the malign character in the Star Wars series, for whom this species is named.