Plumaroides aquilus Diez & Fidalgo

Plumaroides aquilus Diez & Fidalgo , sp. nov.

( Figs 1–4 View FIGURES 1 – 10 )

Diagnosis. This species is easily distinguished from all other species of the genus by its characteristic black coloration.

Description. MALE. Holotype male. Total length 6.0 mm ( paratypes 4.0 to 6.5 mm). Color: Black with dark brown areas as follows: radicle, central area of mandible, distal area of maxillary palpus, seventh tergum in dorsal view, pterostigma. Sculpture: Alutaceous, body with abundant, regular hairs. Head and mesosoma with conspicuous punctures separated by approximately 1 their diameter.

Head. 0.7 x as high as wide, in frontal view; equal to maximum width of the mesosoma between tegulae. Ocellocular distance 2.7 x the diameter of lateral ocellus, postocellar distance 1.4 x ocellocular distance. Antennocular distance 1 x diameter of antennal socket; interantennal distance 2.7 x antennocular distance. Distance between socket and clypeus 0.8 x diameter of socket. Malar space 0.2 x height of eye. Apex of clypeus in frontal view slightly emarginate medially, apical margin recessed, epistomal suture distinct and curved medially ( Fig. 1 View FIGURES 1 – 10 ). Apical setae of clypeus variable in size being the longest as the height of clypeus, medially. Labrum small, distinct in frontal view, lightly emarginated apically. Mandible with three blunt teeth; with setae variable in size, the longest 0.4 x basal width of mandible. Labial palpus with two segments, basal 1.7 x as long as apical. Maxillary palpus with five segments; proportions of segments (length: width): 1.5: 0.5; 1.1: 0.5; 1.7: 0.3; 1.0: 0.4; 1.0: 0.4. Antenna with 13 segments tapering to apex; scape subrectangular, shorter than pedicel and first flagellomere together. Proportion of flagellomeres (lengths), from base to apex: 1.2; 1.2; 1.4; 1.5; 1.3; 1.4; 1.3; 1.3; 1.2; 1.2; 1.9. Flagellomeres with short, decumbent and abundant setae, longest setae nearly 0.2 x as long as width of flagellomere; ovoid sensory plates present on flagellomeres 1 to 10, being more abundant on the first four flagellomeres, in dorsal view.

Mesosoma. 1.6 x as long as wide. Proportions of lengths of mesoscutum, mesoscutellum, metanotum, metapostnotum and propodeum in dorsal view, along median axis: 39: 36: 22: 6: 21. Pronotum not distinct, except for small part of pronotal lobe in front of tegula; ventrolateral angle rounded. Mesoscutum with parapsidal line and notaulus distinct. Metanotum subrectangular, 0.5 x as long as mesoscutum. Propodeum convex, subrectangular in dorsal view, 2.5 x as wide as long; spiracle loop-shaped and separated from the basal margin of the propodeum by a distance less than the length of the spiracle. Wings: Fore wing approximately 2.1 x as long as wide; marginal cell with anterior margin 2.2 x as long as posterior margin, and basal margin slightly curved forward. Hind wing with vannal lobe 3.8 x the length of the submedial cell ( Fig. 2 View FIGURES 1 – 10 ); seven hamuli. Legs: Slender; tibiae and tarsi with scattered weak setae; fore tibia with 15 strong spiniform setae apically and along outer margin; these setae approximately 18 on mid tibia and absent on hind tibia. Tibial spurs 1-2-2; anterior spur curved and weakly pectinate on inner margin; fore basitarsus with shallow strigilar concavity approximately one third as long as basitarsus, bearing strigilar comb of fine setae.

Metasoma. 1.6 x as long as its maximum width. Seventh tergum with subtriangular shape and polished distal zone; lateral carina well developed; longitudinal carina even height from base to apex ( Figs 3, 4 View FIGURES 1 – 10 ).

FEMALE. Unknown.

Type mterial. Holotype 3: Argentina, Province Catamarca, 5 km North Palo Blanco, 23-II-07, Diez, Fidalgo ( MACN). Paratype: 32 3 same data as holotype ( MACN); 3 3, 5 km North Palo Blanco, 8-II-06, Diez, Fidalgo ( MLP); 6 3, 30 km N de Fiambala, 6-II-07, Diez, Fidalgo ( IFML). Province La Rioja, 1 3, RN 27 between San Ramon and Valle Fertil, 14-XII-06, Diez, Fidalgo ( MACN).

Variation. In the marginal cell the anterior margin varies from 2.0 to 2.6 x as long as posterior margin. The coloration varies, with the following parts sometimes lighter: distal region of scape, a thin apical band in tergum 1 to 5, distal regions of trochanter, femur, tibia, tarsus and pretarsus of all legs.

Discussion. Plumaroides aquilus sp. nov. can be distinguished from other species of Plumaroides by: ocellocular distance is 2.7 x diameter of lateral ocellus in P. aquilus sp. nov., while it is 1.6 x in P. andalgalensis and P. brothersi , and 2.0 x in P. tiphlus ; interantennal distance is 2.7 x antennocular distance in P. a q u i l u s sp. nov., while it is 6.7 x in P. andalgalensis , 4.9 x in P. brothersi , and 4.3 x in P. t i p h l u s; vannal lobe is 3.8 x the length of the submedial cell in P. aquilus sp. nov., while it is 2.2 x in P. andalgalensis , 3.5 x in P. brothersi , and 2.6 x in P. tiphlus .

Etymology. This species was named after its characteristic black coloration (Latin aquilus : dark coloration).