Trachysphyrus riojanus Porter, 2008

Porter, Charles C., 2008, New Trachysphyrus Haliday (Hymenoptera, Ichneumonidae) in the albomarginatus species group from northwestern Argentina, Insecta Mundi 2008 (55), pp. 1-9 : 5-6

Trachysphyrus riojanus Porter , new species

( Fig. 2 )

Description. Female Holotype. Color: antenna black with a white band above on flagellomeres 6-9; head, mesosoma and gaster black with dull white and reddish staining on mandible, a white line on upper half of facial orbit and much of frontal orbit, a white line on upper half of hind orbit, dull white on pronotal collar; fore and mid leg with coxa and trochanter black, femur orange, tibia duller orange with faint dusky staining, tarsus dull orange with dusky on tips of segments 1-4 and 5 th segment mostly black; hind leg similar except with some white on tarsomeres 3 and 4; wings dark brown with metallic reflections.

Length of forewing: 8.1 mm. Flagellum slender, cylindric with first segment 3.7 times as long as deep at apex. Clypeus subnasute, weakly and asymmetrically raised in profile, basal face gently curved and apical face strongly concave, 0.3 times as long as base, the faces very distinct in anterior view, separated towards middle by a low ridge. Malar space 0.6 times as long as basal width of mandible. Fore tibia stout but scarcely inflated. Mesoscutum with notauli sharp and narrow, reaching 0.9 times length of mesoscutum; surface shining with some weak transverse wrinkling along notauli and with very dense but largely noncoalescent small, sharp punctures which are a little larger and more discrete on lateral lobes and a little smaller and more crowded on central lobe. Mesopleuron dully shining, densely puncto-reticulate; sternaulus becoming broad and shallow on its apical 0.5 but traceable throughout. Wing venation with areolet large, intercubiti moderately convergent above, second abscissa of radius 0.8 times as long as first intercubitus. Propodeum with spiracle 1.7 times as long as wide; basal transcarina delicate but traceable throughout; apical transcarina faintly developed toward middle, stronger laterally where it is developed into broad, low subcuneate cristae. First gastric tergite with postpetiole strongly expanded, 1.1 times as wide at apex as long from spiracle to apex; dorsal longitudinal carinae distinct but not sharp on apex of petiole and base of postpetiole; surface smooth and polished with very weak micro-reticulation and small widely scattered punctures which are most numerous laterad. Second gastric tergite dully shining with small very numerous tiny crowded punctures that are mostly subadjacent to a little confluent and which emit short, overlapping setae. Ovipositor sheathed portion 0.80 times as long as fore wing, straight, compressed; nodus well developed with a tiny notch at summit, dorsal valve in profile steeply and directly tapering from notch to apex, 0.33 times as long as high at apex.

Variation. Color: white band on flagellomeres 5-9; white markings on head often very faint. Length of fore wing: 6.4-8.7 mm. Flagellum with first segment 3.5-4.0 times as long as deep at apex. Malar space 0.8 times as long as basal width of mandible. Wing venation: second abscissa of radius 0.7-0.9 times as long as first intercubitus. Ovipositor: sheathed portion 0.70 times as long as fore wing; tip 0.30-0.34 times as high a notch as long from notch to apex.

Type Material. Holotype female, ARGENTINA, La Rioja Province, Sierra de Velasco, Santa Vera Cruz , 1700 m, XII-2001, P. Fidalgo, Malaise trap [ IMLA] . Paratypes: 9 females, ARGENTINA , 3 females, La Rioja Province, Sierra de Velasco, Santa Vera Cruz , 1700 m, 15-31-XII-2003, I-2002, P. Fidalgo, Malaise trap [ AEIC, FSCA, IMLA] ; 2 females, Salta Province, Tacuil , 2400 m, 16-31-XII-1968,1- 15-I-1969, Willink, Terán, Stange, Malaise trap [ IMLA] ; 3 females, Salta Province, Yacochuya 1950 m, ca. Cafayate , 16-30- IX-1968, 1-15-X-1969, 16-31-X-1968, 16-31-XII-1969, Willink, Terán, Stange, Malaise trap [ IMLA] .

Relationships. This species is distinctive in its long ovipositor with the nodus conspicuously elevated, sharp and almost percurrent notauli, dully shining second gastric tergite with tiny crowded punctures and densely overlapping setae, and entirely black gaster. Only T. blanchardi has the ovipositor equally long but this is an adaptive character of little phylogenetic significance and, as indicated in the key, T. riojanus has several distinctive features which suggest that it is not closely related to any other species of its group.

Figures

Figure 2. Trachysphyrus riojanus, female, paratype. Santa Vera Cruz, La Rioja, Argentina. Lateral view of entire insect.