Bradynobaenus riojanus Torréns and Roig-Alsina, 2009

Torréns, Javier & Roig-Alsina, Arturo, 2009, Description of a new species of Bradynobaenus (Hymenoptera: Bradynobaenidae) from Argentina, with a key to the females of the genus, Zootaxa 2047, pp. 63-68 : 64-66

Bradynobaenus riojanus Torréns and Roig-Alsina , New Species

( Figs. 1–11 )

Type material. Holotype female. ‘ Argentina, La Rioja: Vinchina, 4–XI–1970, G. Williner’ deposited in MACN. Paratype: La Rioja: Udpinango, 16/ 25–III–2006, P. Fidalgo, G. Fidalgo and J. Torréns (1 female, MACN).

Diagnosis. This species is closely related to B. chubutinus . Both species are distinguished from all other Bradynobaenus by having an oblique row of setae on the mesonotum, which runs from the antero-lateral angle towards the midline, reaching posteriorly beyond the middle of the mesonotum ( Figs. 4, 5 , 8 , ols), and by having a mesopleural line of setae, which is strongly arcuate backwards in front of the pronotal lobe ( Fig. 11 , mls). Bradynobaenus riojanus is readily distinguished from B. chubutinus by the proximal tooth of the mandible without a basal thickening ( Fig. 2 ) and by the yellowish to reddish brown color of the scape, legs except tarsi, and the basal four metasomal terga, which are black in B. chubutinus .

Holotype female. Length, 11.0 mm; maximum width 3.2 mm. Coloration: head, scape, mesosoma, legs except tarsi, and metasoma pale yellowish-brown; pedicel, flagellum, and tarsi whitish; apex and teeth of mandible black.

Head. Depressed, in dorsal view 2.1X wider than long ( Fig. 1 ). Short, transverse clypeus with median part projected above labrum more or less straight ( Fig. 10 ). Scape as long as following five flagellomeres; proximal four flagellomeres cylindrical, following flagellomeres slightly compressed ( Fig. 9 ). Mandible as long as length of head; with three distal teeth in a row, the intermediate the smallest, the proximal without basal thickening ( Figs. 1, 2 ); basal end of median cutting edge straight. Head with dense rows of setae, as follows: a U-shaped row of whitish setae on upper, flattened surface of scape; basal group of dense whitish setae on lower surface of scape; short row of whitish setae on outer half of pedicel; dense row of whitish setae bordering dorsally antennal socket; oblique row of whitish setae from base of mandible towards frons, running between eye and antennal socket; short row of whitish setae above eye; row of short, whitish setae along margin of clypeus; row of dense, long, setae from base of mandible and surrounding all the head along subgenal area and vertex, setae whitish on subgenal area, reddish brown on vertex; row of short, reddishbrown setae on postoccipital suture.

Mesosoma. Depressed, in dorsal view 1.1X longer than wide ( Figs. 6 , 8 ). Pronotum in dorsal view 2.0X wider than long; anterior margin of dorsal surface with irregular band of strong, separated punctures bearing redish-brown setae, this band continued laterally, but antero-lateral angle with punctures dense, coalescent, and bearing whitish setae, from antero-lateral angle to just below pronotal lobe with band of dense punctures and whitish setae; lower lateral margin of pronotum also with punctures and whitish setae; lateral surface smooth between setose areas. Mesonotum 2.0X wider than long; at each side with oblique line of punctures and reddish-brown setae, running from antero-lateral angle towards midline, and reaching posteriorly beyond middle of scutum ( Fig. 8 ); meso-metathoracic suture with dense row of reddish-brown setae. Fused metanotum and propodeum vertical, surface smooth, polished. Area between upper end of meso-metapleural suture and propodeal spiraculum, swollen, bearing small triangular depression close to mesonotal margin. Mesopleural line of setae arcuate backwards in front of pronotal lobe; on middle of mesopleuron forming densely punctate band, which is connected by a few or no punctures with line of setae in front of mid coxa ( Fig 11 ); setae on mesopleuron whitish; surface of mesopleuron smooth and polished anteriorly and posteriorly to line of setae. Meso-metapleural suture distinct; separation of metapleuron and propodeum indicated by feeble depression. Femora with long, whitish setae posteriorly; tibiae with rows of whitish setae; spiniform setae on tibiae and tarsi also pale. Foreleg: tibia on posterior margin with four apical spiniform setae; basitarsus apically broadened, posterior margin with row of eight stout, flattened, spiniform setae, increasing in length distally, apical one as long as combined length of following two tarsomeres; anterior margin at apex with two stout setae, longer than following tarsomere; tarsomeres II and III at apex with a single posterior flattened spiniform seta, longer than following tarsomere, and two strong anterior setae; tarsomere IV with one apical seta. Mid leg: dorsal margin of tibia on proximal half with six short spiniform setae, apex of tibia with spiniform setae surrounding insertion of tarsus in a single row; tarsomeres I, II and III, with spiniform setae surrounding insertion of following tarsomere. Hind leg: tibia on anterior and posterior surfaces with longitudinal row of setae close to upper margin, but upper margin bare, polished, without any punctures. Distribution of spiniform setae similar to that of mid leg.

Metasoma. Depressed, in dorsal view 1.8X longer than maximum width ( Figs. 4, 6 ). First tergum with anterior vertical surface entirely covered with setae; posterior dorsal surface bare. Second to fifth terga with dense row of setae on posterior margin. Sixth tergum with continuous carina enclosing dorsal surface; carina laterally without distinct tooth. First to third sterna with setae all over their surface, fourth to sixth sterna with setae restricted to posterior margin.

Variation. The paratype differs from the holotype as follows. Length 14.0 mm, maximum width 4.0 mm. Color of integument: head, scape, pedicel, mesosoma, legs except tarsi, and metasoma reddish brown; metasomal terga darker apically. Foretibia on posterior margin with three short, apical spiniform setae. Basitarsus of foreleg on posterior margin with row of nine stout, flattened, spiniform setae. Dorsal margin of mid tibia on proximal half with three short spiniform setae.

Etymology. The specific name refers to the province where the specimens were collected.

Figures

FIGURES 1 – 7. Bradynobaenus riojanus n. sp. (female) and Bradynobaenus chubutinus (female): 1, B. riojanus, head and mandible (dorsal view). 2, B. riojanus, mandible (dorsal view). 3, B. chubutinus, head and mandible (frontal view). 4, B. riojanus, habitus (dorsal view). 5, B. chubutinus, habitus (dorsal view). 6, B. riojanus, habitus (lateral view). 7, B. chubutinus, habitus (lateral view).

FIGURES 8 – 11. Bradynobaenus riojanus n. sp. (female): 8, mesosoma (dorsal view); 9, antenna (dorsal view, rows of points in the scape correspond to setae); 10, clypeus (frontal view); 11, mesopleuron (lateral view). (mls = mesopleural line of setae, ols = oblique line of punctures and setae).