Azteca quadraticeps, Longino, J. T., 2007

Longino, J. T., 2007, A taxonomic review of the genus Azteca (Hymenoptera: Formicidae) in Costa Rica and a global revision of the aurita group., Zootaxa 1491, pp. 1-63 : 45-46

Azteca quadraticeps new species

Figures 3,4A,5,6A,6B,8.

Holotype alate queen: Costa Rica, Prov. Limón, Tortuguero , 10°32'N, 83°31'W, 5m , 1 Jul 1985 (J. Longino #0389-s) [ INBC, specimen code JTLC000005714 ].

Paratypes: same data as holotype; 1 alate queen [ JTLC000005715 , MCZC], 1 alate queen [ JTLC000009450 , USNM].

Measurements of holotype. HLA 1.84, HLB 1.81, HW 1.72, AHW 1.28, SL 1.19, EL 0.46, OC 0.09, MTSC 33.

Diagnosis. Queen with the same characters as A. flavigaster , differing only in the larger size. It differs from A. velox in the more quadrate head shape, less narrowed anteriorly (Fig. 6B) and with less rounded sides (Fig. 3).

Queen characters. Measurements (n=6): HLA 1.78 (1.70-1.84), HW 1.71 (1.62-1.79), SL 1.16 (1.11- 1.19), CI 96 (93-98), SI 65 (64-66).

Palpal formula 6,4; ocelli small; middle and hind tibia with prominent pectinate apical spur; dorsal surface of mandible with small piligerous puncta, setae in puncta short, subdecumbent, interspaces between puncta smooth and shiny on apical half of mandible, gradually becoming faintly microareolate at base; medial and lateral clypeal lobes at about same level; head subquadrate, posterior margin not strongly cordate, very shallowly excavate; petiolar node tall, strongly compressed into thin scale at apex; posteroventral petiolar lobe evenly convex from front to back; scape with abundant erect setae, about as long as one half maximum width of scape; middle and hind tibia with abundant erect setae, longest of these about as long as one third maximum width of tibia (MTSC 25-35); sides of head without erect setae; posterior margin of head with erect setae; pronotum with erect setae on posterior margin; mesoscutum, scutellum, and propodeum with abundant erect setae; petiolar node with rim of erect pubescence and sparse longer erect setae, 1-2 pairs of erect setae extending above apex in profile, posterior border of sternal lobe of petiole with uniform layer of short erect setae; gastral terga with sparse long erect setae; most of face dark brown, with lighter orange coloration restricted to anterior malar area near mandibular insertions and antennal fossa.

Etymology. The name refers to the somewhat quadrate shape of the head. Its close relative, A. velox , has more rounded sides of the head.

Range. Costa Rica.

Biology. This species is known only from queens. They have been collected in lowland to mid-elevation (700m) rainforest in the Atlantic lowlands of Costa Rica.

Comments. Azteca quadraticeps is in a cluster of species that are difficult to distinguish: A. flavigaster , A. nigra , A. sericeasur , and A. velox . It is likely that the workers of A. quadraticeps have been collected and either left unidentified or misidentified. One possibility is that A. quadraticeps is an Atlantic slope version of A. flavigaster , and Atlantic slope worker collections identified as A. flavigaster are A. quadraticeps . Other possibilities are that A. quadraticeps workers masquerade as A. velox , A. nigra , or smaller workers of A. sericeasur .

Additional material examined. COSTA RICA: Guanacaste: Estacion Pitilla, Guanacaste Cons. Area , 10°59'N, 85°26'W, 700m , 1- 30 Jan 1989 (coll. GNP Biodiversity Survey) - queen [ INBC] ; Fca. Pasmompa, 5Km SW Santa Cecilia , 11°01'N, 84°34'W, 400m , 1- 30 Mar 1989 (coll. GNP Biodiversity Survey) - queen [ INBC] ; same locality, Mar 1989 (coll. PNG Inventario de Biodiversidad) - queens [ INBC] ; Heredia: 11km ESE La Virgen , 10°21'N, 84°03'W, 300m , 12 Feb- 18 Apr 2004 (ALAS) - queens [ INBC] .