Mesembrinella bolivar ( Bonatto, 2005 )

Whitworth, Terry L. & Yusseff-Vanegas, Sohath, 2019, A revision of the genera and species of the Neotropical family Mesembrinellidae (Diptera: Oestroidea), Zootaxa 4659 (1), pp. 1-146 : 58-59

Mesembrinella bolivar ( Bonatto, 2005)

( Figs 6, 37–38, 127–128, 206, 462)

Giovanella bolivar Bonatto in Bonatto & Marinoni, 2005: 886 . Holotype male (USNM), examined. Type locality: Kavanayen , Bolivar, Venezuela.

Giovanella bolivar: Kosmann et al. (2013: 77) ; Wolff et al. (2013b: 132); Marinho et al. (2017: tab. 1); Velásquez et al. (2017: 108).

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

Diagnosis. A medium-sized blue-brown fly, the single specimen available measured 11 mm in length. Legs mostly brown, except femora orange with apical 1/4 reddish-brown vs. legs entirely brown in M. carvalhoi ; spiracles orange vs. anterior spiracle yellow-orange and posterior spiracle dark brown in M. carvalhoi ; wing infuscated along anterior edge of costa up to R 2+3. Male terminalia with cercus and surstylus not widely separated in lateral view; base of cercus not enlarged, without dense comb of setae ( Fig. 37).

Redescription. Male [holotype]. Head. Frons narrow, 0.02/1 of head width at narrowest, narrower than width of anterior ocellus; fronto-orbital slender with silvery tomentum ventrally and orange tomentum dorsally; dorsal 2/3 of parafacial silvery, ventral third orange; gena orange with faint whitish tomentum, covered with fine tan setae and typical horizontal row of stout setae extending from postgena through to lower parafacial; postgena with silvery tomentum and few dark setae anteriorly, posteriorly with long orange setae; occiput with fine yellow setae, dorsal third dull black, remainder with whitish tomentum; antenna: pedicel pale orange with short brown setae, first flag- ellomere brown with yellowish tomentum, arista with proximal 1/3 orange and distal 2/3 black; eye with median facets about 3x size of lateral facets; frontal setae ascending about 30% of distance to vertex; ocellar triangle small, anterior ocellus slightly larger than posterior ocelli; supravibrissal setae on facial ridge very sparse, forming a small cluster of 3 or 4 setae at base.

Thorax. Dorsum brown with pale tomentum appearing pale bluish on prescutum; scutellum brown without tomentum or stripes; pleura bluish-orange with pale tomentum; chaetotaxy: ac 0:0, dc 2:3; ia 0, ph 0, ppn 2x 2, kat 1:1, meron with long, slender tan setae; 1 pair converging ap, 1 lat, 1 bas, 0 disc, no other setae; [subscutellum not visible on specimen]; spiracles yellow-orange, anterior spiracle with a long, narrow opening gradually widening above ( Fig. 6), instead of the typical broad, oval opening seen in other species-groups ( Fig. 5); legs: femora entirely orange except brown distally, tibiae and tarsi brown. Wing with distinct dark infuscation along anterior edge from costa to vein R 2+3; vein M, crossvein dm-cu and vein CuA dark shaded; rest of wing somewhat darkened; section IV 0.11 of section III; subcostal sclerite pale orange with pubescence; basicosta and tegula brown; discs of upper and lower calypters light tan; rims dark brown with long brown setae.

Abdomen. T1–3 yellow-orange, T4–5 brown with whitish tomentum. T1+2 with cluster of stout lateral marginal setae; T3–T5 each with pair of lateral marginal setae; T4 and T5 with row of stout setae on posterior margins; disc of T5 without mid-dorsal horizontal row of stout setae, with fine setae only. Terminalia [the holotype’s terminalia were already dissected and in marginal condition, as shown in Figs 37–38]. In lateral view with surstylus curved slightly backward, epandrium of moderate size ( Fig. 37); in posterior view base of cercus broad, tapered steadily to rounded tips ( Fig. 38); phallus in lateral view with epiphallus of moderate size and gradually curved backward ( Fig. 127); in dorsal view, hypophallic lobes narrow ( Fig. 128); T6, STS7+8, pre- and postgonite and ejaculatory sclerites as in Fig. 206.

Female. [No female specimens were examined by us. Bonatto & Marinoni (2005) examined two females and described some characters, but they did not illustrate them. They stated that the spermathecae are filiform and the sternites oval.]

Type material examined. HOLOTYPE ³* ( Venezuela , Bolivar; USNM; Fig. 462), labeled: VENEZUELA: Bolivar / Kavanayen 1000m. / Aug. 8, 1970 / R. E. Dietz IV, leg. ; HOLOTYPE / Giovanella bolivar / S.R. Bonatto det. [red label]; USNMENT01288292.

Remarks. Specimen in good condition, rear part of T4 and all of T5 removed and dissected by Bonatto; T5 and terminalia in small plastic vial under specimen on pin; portion of T4 missing.

Distribution. Venezuela.

Remarks. Only the holotype male was examined. Bonatto & Marinoni (2005) provided a brief description of the female but did not illustrate any characters. The sketch of the anterior thoracic spiracle of M. bolivar provided by Bonatto & Marinoni (2005) is misleading: it is shown as a narrow, uniform slit, but examination of the holotype showed that it is actually in the shape of a narrow V ( Fig. 6). This unusual shape is also found in M. epandrioaurantia sp. nov. and M. woodorum sp. nov. However, the epandrium, cerci and surstyli are very different in these two species ( Figs 31–34) compared to M. bolivar ( Figs 37–38). No specimens were barcoded.