Mesembrinella decrepita Séguy, 1925

(Figs 39–40, 129–130, 207, 250, 293, 337, 379, 422, 488)

Mesembrinella decrepita Séguy, 1925: 195 . Holotype male (MNHN), not examined. Type locality: Colombia.

Huascaromusca decrepita: Peris & Mariluis (1984: 255); Kosmann et al. (2013: 77); Wolff & Kosmann (2016: 867); Marinho et al. (2017: tab. 1); Velásquez et al. (2017: 108).

Mesembrinella decrepita: Cerretti et al. (2017: tab. 2).

Diagnosis. A medium-sized blue-black fly averaging 9.6 mm (9–10/5) in length. Postpronotal lobe with 3x 3 setae; subcostal sclerite bare; femora pale orange. Male frons about 0.074 of head width at narrowest; terminalia distinctive, with broad cerci in posterior view (Fig. 39). Female T6 distinctive, with broad division midway and of OV shape; T7 and T8 narrowed midway (Fig. 293).

Redescription. Male. Frons broad, 0.074 (0.07–0.08/5) of head width at narrowest, almost as broad as width of first flagellomere; fronto-orbital dark with silvery tomentum; frontal setae ascending about 60% of distance to vertex; frontal vitta: upper 2/3 black, lower 1/3 orange; parafacial orange with pale tomentum; gena orange with horizontal row of stout dark setae and scattered smaller dark setae; postgena orange with long pale setae; occiput dark with pale tomentum and pale setae; median occipital sclerite shiny black; antenna orange; arista tan; palpus typical; eye with median facets slightly larger than lateral facets; ocellar triangle medium-sized, anterior ocellus about 2x size of posterior ocelli; supravibrissal setae on facial ridge ascending about 1/5 of distance to antennal base.

Thorax. Dorsum and pleural areas blue-black with whitish tomentum; chaetotaxy: ac variable, most commonly 1:1, then 2:1, then 0:1, sometimes a seta missing on one side, dc 2:3, ia 0, ph 1, ppn 3x 3, kat 2:1, meral setae typical, 1 pair crossed ap, 0 sa or lat, 1 stout bas, 1 weak pb, 1 disc; subscutellum moderately developed; spiracles orange, mediumsized. Wing hyaline, with section IV 0.17 of section III; subcostal sclerite bare; basicosta and tegula orange; calypters brown with brown rims; rim of upper calypter with short dark setae, rim of lower calypter with long pale setae.

Abdomen. T1+2–T3 shiny blue with whitish tomentum, T4–5 shiny blue with little tomentum; T1+2–3 with pair of lateral marginal setae; T4–5 each with row of marginal setae, the row on T5 weaker; disc of T5 with middorsal horizontal row of stout setae, rest of disc with sparse, fine setae. Terminalia. In lateral view surstylus slender, curving slightly forward, cercus with apical hook (Fig. 39); in posterior view, base of cerci broad, tapering to divergent tips (Fig. 40); phallus in lateral view with epiphallus curved backward, basiphallus extended anteroventrally (Fig. 129); in dorsal view, hypophallic lobes very narrow (Fig. 130); T6, STS7+8, pre- and postgonite, ejaculatory sclerite and ST6 as in Fig. 207; sternites as in Fig. 250.

Female. Similar to male except frons 0.245 (0.23–0.25/4) of head width at narrowest. T6 of RV shape, broadly divided midway, T7 continuous, weakened and translucent midway, T8 broad with suture midway (Fig. 293). ST6–8 and hypoproct as in Fig. 337; spermathecae filiform (Fig. 379); ST1–5 as in Fig. 422.

Material examined. Venezuela, Distrito Federal. 1 ♂*, 1 ♀ ♦* (TLW378), 7 ♂♂, Parque Nac. Avila, 1800 m, 28.ii.1971, G. & M. Wood (CNC) . Lara. 1 ♂♦ (TLW258), 1 ♀ ♦ (TLW257), 8 km. S Sanare, Yacambu Natl. Park 1600 m, 27.xii.1985, P. Kovarik & R. Jones (TAMU) . Merida. 1 ♂*, 10 km E. Tobay, 2000 m, 28.iv.1981, H. Townes (CNC) . Yaracuy. 1 ♂, Corceorote Sector El Candelo, 1650 m, 10°36ʹ888ʺN–68°82ʹ628ʺW, 17–20.x.2001, T. Interceptacion, R. Briceño, A. Chacán, J. Clavijo, F. Díaz, R. Paz, E. Arcaya & L. Joly (MJMO) ; 1 ♂♦ (TLW259), 1 ♀, Edo. Lara, P.N. Yacambu, “El Blanquito”, 9°63N, 69°53W, 29.i.2007, A. Martínez (MJMO) .

Distribution. Venezuela. Bonatto (2001) also listed it from Colombia. The listing of this species from Mexico in Marinho et al. (2017: tab. 1) was an error (M. Marinho, pers. comm.).

Remarks. The only specimens examined during this study were from Venezuela. Four specimens (TLW 252– 259, TLW 378) were barcoded, and they clustered together (Fig. 488).