Pelecinobaccha hirundella (Hull, 1944) Hull, 1944

Miranda, Gil Felipe Gonçalves, Marshall, Stephen A. & Skevington, Jeffrey H., 2014, Revision of the genus Pelecinobaccha Shannon, description of Relictanum gen. nov., and redescription of Atylobaccha flukiella (Curran, 1941) (Diptera: Syrphidae), Zootaxa 3819 (1), pp. 1-154 : 46-47

Pelecinobaccha hirundella (Hull, 1944) comb. nov.

Map 12. Figure 30 .

Baccha hirundella Hull, 1944 — Hull, 1944b: 59. Type locality: Brazil, Santa Catarina, Nova Teutônia. Holotype female AMNH. Hull, 1949a: 155 (redescription), 212 (fig. 99, female abdomen).

Ocyptamus hirundella . Thompson et al., 1976: 20 (catalog citation).

Male. Head: Dark brown. Face pale on lateral ¼. Gena dark brown. Lunule pale above antennal insertions, central maculae connected by a narrow to wide median dark vittae to frontal triangle color. Frontal triangle usually entirely dark, some specimens pale laterally, white-silver pollen continuous from face restricted to lateral margin except around eye contiguity. Vertical triangle with 3 rows of pile, but most pile concentrated in a single median row; ocellar triangle ~1.5 times its length from posterior eye margin. Eye contiguity as long as vertical triangle length. Eye with posterior indentation slightly dorsal to level of antennal insertion. Antennal insertions almost separated, ventral margin dorsal extension unsclerotized dorsally. Dorsal ¼ of occiput with 2 rows of black pile, anterior row shorter; middle ½ with 2–3 rows of white scale-like pile, posterior row longer, with some simple black pile on anterior row; ventral ¼ with 2–3 rows of scale-like white pile.

Thorax: Scutum dark brown, with white-pollinose weak pair of sub-median vittae and one weak median vitta; scutum mainly black pilose except white pilose anterior to callus until transverse suture, and callus with white and black pile intermixed, pile slightly longer on notopleuron; scutum anterior row of shining white pile interrupted in the middle, pile as long as remainder pile of scutum. Scutellum dark brown, with sparse short black pile, subscutellar fringe pile long and white. Pleuron white pilose and dark brown, some specimens slightly lightened on posterior ½ of posterior anepisternum. Plumula long, white. Calypter light yellow. Halter brown, capitulum orange.

Wing: Basal ⅔ dark (cells bc, c, sc, r, basal ¾ of r1, slightly less than basal ⅔ of r2+3, basal ½ of r4+5, bm, basal ¾ of dm, cua1 and cu p), entirely microtrichose; alula basally 2 times and apically 4 times as broad as c cell, hyaline, entirely microtrichose.

Legs: Proleg brown, slightly lightened on interior surface of profemur and basal ½ of protibia. Mesoleg brown, apex of mesofemur pale, basal ½ of mesotibia slightly lightened. Metaleg brown, base of metatibia pale, apical ¼ or 1/5 of metabasitarsomere until 4th metatarsomere pale.

Abdomen: Dark brown; ~3.5 times as long as thorax. First tergite white pilose, except pile black dorsoapically. Second tergite long, length ~3.5 times minimum width, with long triangular maculae of dull black pollen subapically pointing to the base; 2nd tergite mainly black pilose, except white on baso-lateral ⅔, and with long, erect pile laterally, except short and appressed dorsally. Third tergite trapezoidal, usually pale on baso-lateral ½ and with large triangular macula of dull black pollen medially, which sometimes has a medial pair of sub-shining vittate maculae; 3rd tergite mainly with appressed black pile, except slightly longer and white on baso-lateral corners. Fourth tergite quadrate, slightly longer than wide, and with appressed black pile; remaining characters as on 3rd. Fifth tergite rectangular and wide, entirely dark brown; remaining characteristics as on 4th. Genitalia: Cercus with 1 regular row of pile on medial margin and 2–3 irregular rows on lateral margin. Surstylus directed anteriorly, with strong setulae (around 16) on ventral ½, with very little of the dorsal thin sclerotized layer, pilose on basal ½ of the dorsal surface. Subepandrial sclerite trapezoidal and short. Hypandrium with ventral notch extending to anterior ½.

Distiphallus smooth and anterior surface curved anteriorly. Postgonite with pile mainly on ventral surface, ventral surface straight, extended baso-ventrally, dorsal surface slightly concave with small convexity before apex; postgonite apex convex anteriorly, with slightly convex ventral extremity and acute dorsal extremity.

Female: Like male except: Frons pale laterally on ventral ⅔. Vertex with one central row of shorter pile directed forward; ocellar triangle ~2 times its length from posterior eye margin and 1.5–2.5 ocelli-width from lateral eye margin. Scutum pile shorter, entirely white on notopleuron. Scutellum with shorter pile, subscutellar fringe pile very short and black to absent. Pleuron pale on posterior ½ of posterior anepisternum and dorsoposterior of the katepisternum. Wing darker (basal ⅔ of r2+3, ⅔ of r4+5 and most of dm). Basal ½ of protibia and basal ⅔ of mesotibia distinctly pale. First tergite pile shorter. Second tergite pile very short and appressed. Third and 4th tergites with narrower dull pollinose region and without pale baso-lateral margin. Fourth tergite rectangular and wide. Sixth segment conical short, 1.3 times wider than long at base and 1.4 times as long as 5th tergite. Genitalia: 7th tergite with apex “open”, basal extensions weakly sclerotized and as long as the 6th segment; 7th segment lateral sclerite right triangle shaped, acute baso-ventrally. Eighth tergite unsclerotized medially appearing as a pair of sclerites, apex wide, basal crest short and weakly sclerotized; 8th sternite whole, weakly sclerotized medially.

Length. 8.5–10mm; wing 7–8mm.

Distribution. Brazil (Santa Catarina).

Material examined. BRAZIL. Santa Catarina, Nova Teutônia, 300–500m, 27°11'S 52°23'W, Holotype hirundella Hull [red label], 10 Oct 1936, F. Plaumann (1 ♀, Holotype Baccha hirundella , AMNH); ..., Nov– Jan 1964–6 & 1969– 70 F. Plaumann (7 ♂, CNC Diptera 161175 –81, 9 ♀, CNC Diptera 161167 –74 & MZUSP).

Comments. The pile on the occiput was missing from the head of the type specimen of B. hirundella , but overall it agrees with this redescription.

Figures

FIGURE 30. Pelecinobaccha hirundella (Hull, 1944). a – d. Female genitalia: a. Apex, oblique dorsal. b. 7 th tergite, dorsal. c. 7 th segment, lateral. d. Apex, lateral. e – h. Male genitalia: e. Epandrium, lateral. f. Epandrium, ventral. g. Hypandrium, lateral. h. Hypandrium, ventral. i. Holotype, habitus, dorsal. 8 tg: 8 th tergite, 10 tg: 10 th tergite, cerc: cercus, s scl: subepandrial sclerite.