Brachygasterina valdiviensis ( Pamplona & Couri, 2000 )

De Carvalho, C. J. B. & Pont, A. C., 2006, Taxonomy, cladistics and biogeography of the South American genus Brachygasterina Macquart (Diptera: Muscidae), Zootaxa 1151, pp. 1-26 : 13-14

Brachygasterina valdiviensis ( Pamplona & Couri, 2000) ( Figs 4 , 9 )

Palpibracus valdiviensis Pamplona & Couri, 2000: 1 .

Diagnosis

This species is similar in its generally dark metallic violet­blue body colour to most species of Brachygasterina but the parafacial in the female at its narrowest point is less than 0.2 of width of first flagellomere, which is the narrowest among the species of the genus ( Fig. 9 ). It is closely related to B. violaceiventris but can be distinguished by the presence of a dorsal preapical seta on fore tibia and by the number of spermathecae: two in B. valdiviensis and three in B. violaceiventris ( Soares & Carvalho 2004) .

Redescription

Female. Head: frons broad, at narrowest point 0.36 of head width ( Fig. 4 ). Eye with short and sparse hairs; when the head is viewed from the front, the hairs are about as long as width of arista at base. Fronto­orbital plate matt, blackish; parafacial, face and gena brownish­grey pruinose; occiput metallic blue to violet. Seven pairs of frontal setae; 2 reclinate orbital setae. Facial ridge with setulae reaching almost to level of tip of first flagellomere. Parafacial at narrowest point less than 0.2 of width of first flagellomere.

Gena broad, in lateral view at least 0.9 of first flagellomere width. Proboscis mainly shining, dusted behind. Palpus black.

Thorax. Ground­colour subshining dark metallic violet­blue, dulled by pruinescence in posterior view. Mesonotum with 4 stripes. 2+3–4 well­developed acrostichals; 2 strong posterior intra­alars, 1 weaker; prealar strong, subequal to anterior notopleural seta; notopleuron with sparse setulae. Scutellum laterally setulose; with strong apical, basal and lateral setae, and corresponding weak setae on disc. One strong proepisternal seta and 3 setulae; 3 strong proepimeral setae and many long setulae. Katepisternals 2+3. Katatergite distinctly setulose.

Legs. Dark brown. Fore tibia without posterior seta. Mid femur with 1 short anterior and 3 posterior preapical setae. Mid tibia with 3 posterior setae, without anterodorsal or ventrals. Hind femur with a row of strong anteroventral setae, the last 4 stronger; a row of strong posteroventral setae in basal half; 2 anterodorsal and 3 anteroventral setae; dorsal preapical strong, anterodorsal preapical weak, without posteroventral apical.

Wing. Smoky, veins dark brown. Veins bare, except costa. Cross­vein dm­cu very sinuous. Vein M running straight to wing margin. Calypters dark brown, lower one slightly longer than upper one. Knob of haltere dark brown.

Abdomen. Subshining metallic blue­violet, matt from some points of view. Sternite 1 bare.

Ovipositor: see Pamplona and Couri, 2000: figs 1–2. Two spermathecae ( Pamplona & Couri 2000: fig. 3).

Measurements (n=1): Body length, 9 mm. Wing length, 7.9 mm.

Remarks

We examined only one paratype. The holotype female is in MNRJ, and six other paratypes are in MNRJ and CFUA. The type specimens were collected in traps in a rural area, using a dead rat as bait ( Pamplona & Couri 2000).

Geographic distribution

Chile.

Figures

FIGURES 1 – 5. Female head, frontal view. 1. Brachygasterina andina. 2. B. major. 3. B. stuebeli. 4. B. valdiviensis. 5. B. violaceiventris. Scale bar: 1 mm.

FIGURES 6 – 12. Head, lateral view. 6. Female, Brachygasterina andina. 7. Female, B. major. 8. Female, B. stuebeli. 9. Female, B. valdiviensis. 10. Female, B. violaceiventris. 11. Male, B. major. 12. Male, B. violaceiventris. Scale bar: 1 mm.