Pelecinobaccha invisibilis

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 : 49-50

Pelecinobaccha invisibilis Miranda sp. nov.

Map 5. Figure 6 .

Type locality. Brasil, Rio de Janeiro, Petropolis, R. Ueter, 22°30.278'S 43°10.940'W. Holotype female CNC.

Male. Head: Shining black. Face with lateral ¼–1/5 and dorsal to oral margin pale. Lunule with small pale area above antennal insertions and slightly rugose. Frontal triangle shiny, pale laterally on ventral ⅓ or until eye contiguity, with white pollen laterally connected to pollen from face, pile longer close to eye contiguity; frontal prominence slightly protuberant. Vertical triangle with 1 row of black pile; ocellar triangle ~1.5 times its length from posterior eye margin. Eye contiguity ⅔ the length of the vertical triangle. Eye with posterior indentation ventral to the antennal insertion. Antennal insertions confluent, ventral margin has a short dorsal extension. dorsal ¼ of occiput with sparse white pollen, otherwise occiput covered by dense white pollen; dorsal ¼ of occiput with 1 row of simple black pile, sometimes with an anterior row of very short pile, middle 2⁄4 with 2–3 rows of white, scale-like pile, anterior rows shorter; ventral ¼ with 2 rows of white, scale-like pile.

Thorax: Scutum shining black, sparse white-pollinose anteriorly and on notopleuron; scutum with short and mostly black pile, except white pilose laterally, and in an irregular row anteriorly; notopleuron with very short pile. Scutellum shining black, small (½ the width of the scutum), with very short white pile, subscutellar fringe absent. Pleuron black, pale on posterior margin of posterior anepisternum and dorso-posterior katepisternum; pleuron with very short, appressed, sparse, white pile, metepisternum with inconspicuous pile, katatergite with long microtrichosity mainly on posterior ½. Plumula absent. Calypter white, with very short and sparse pile on fringes, ventral lobe narrow. Halter white; metaepimera extended dorso-posteriorly to metacoxa, and with apices approximated.

Wing: Entirely hyaline, bare on cell bc, basal ¾ of c, basal ⅓ of r, basal ¼ of bm and base of cu p, cu p cell narrow; alula absent.

Legs: Proleg and mesoleg pale, coxae, 4th and 5th tarsomeres brown, dorso-apical ⅓ of femora sometimes light brown; white pilose. Metaleg dark brown, basal ⅔ and apex of metafemur and basal ¼ of metatibia pale; pile pale laterally on metacoxa, on metatrochanters and on pale regions.

Abdomen: Dark brown; ~7.5 times as long as thorax; whole abdomen with short, appressed, black pile. First tergite pale on lateral extremities, and mostly bare except for sparse short white pile laterally adn long pile dorsolaterally. Second tergite very long and narrow, length 15 times minimum width, with pair of baso-lateral pale maculae and a subapical lateral pale fasciate maculae that almost meet dorsally; 2nd tergite pile sparse and black, exccept white laterally. Third tergite very long and narrow, slightly expanding towards apex, length 14 times minimum width, with lateral pair of small fasciate pale maculae medially; 3rd tergite pile scarce and white on basal ½. Fourth tergite trapezoidal and long, length 2.8 times minimum width, with lateral sub-basal pair of pale rectangular maculae. Fifth tergite rectangular and wide. Genitalia: Cercus with 2 rows of pile on medial margin and 2 rows on lateral margin. Surstylus oval with medial curved fold on basal ⅔, directed ventrally, with setulae ventrally, thicker and concentrated on apical margin (around 11), thinner and sparse on remaining of surface (around 13) with a few pile medially on the dorsal surface. Subepandrial sclerite rectangular and wide with small baso-lateral projections. Hypandrium oval on basal ½, wider and quadrate on apical ½, with ventral rounded notch on anterior ¾. Phallapodeme ½ the size of the hypandrium, mostly weakly sclerotized, apex and apico-dorsal ⅔ well sclerotized. Basiphallus with blunt posterior extremity; distiphallus with anterior surface straight. Postgonite with ventral surface straight, dorsal surface slightly concave, apex convex anteriorly, with acute dorsal extremity and, slightly extended, oval ventral extremity.

Female: Like male except: Frons of normal width, pale on baso-lateral ½. Ocellar triangle ~1.5 times its length from posterior eye margin and ~3 ocelli-width from lateral eye margin. Second and 3rd metatrochanters light brown. Fifth tergite rectangular and long. Sixth segment divided into tergite and sternite. Genitalia: 7th tergite with acute anterior margin, basal extensions ⅔ the length of the 6th segment; 7th segment lateral sclerite triangular. Eighth tergite entirely sclerotized, apex with a pair of acute extremities, basal crest short, 8th sternite unsclerotized medially. Tenth tergite large and distinct, fused to the dorsal margin of the cerci, forming a short, ventral, acute projection close to cercus. Cercus lanceolate and directed ventrally, with 1–2 rows of pile on apical margin.

Length. 9.5mm; wing 5.5mm.

Distribution. Brazil (Rio de Janeiro, Santa Catarina).

Primary type. Holotype: Female in good condition, double-mounted, with genitalia dissected and placed in a plastic tube pinned with the specimen. Holotype labels: ‘Petropolis // R. Ueter’ ‘sp.- [handwritten] // Det. // F.M.Hull’ ‘Frank M. Hull // Collection // C.N.C. 1973’ ‘CNC Diptera 161196 ’ ‘ Holotype // Pelecinobaccha // invisibilis // Miranda’ [red label].

Paratypes. UNKNOWN. [no label] (1 ♂, CNC Diptera 161194). BRAZIL. Santa Catarina, Nova Teutônia, 300–500m, 27°11'S 52°23'W, Nov 1969, F. Plaumann (1 ♂, CNC Diptera 161195).

Comments. This species resembles the Ocyptamus stenogaster species group in having a slightly rugose frontal triangle/frons, long slender abdomen and no alula. However, the face of Pelecinobaccha invisibilis is more extensively dark and the female genitalia are typical of Pelecinobaccha ( Figs. 6 a–d).

Etymology. The specific epithet is an adjective for ‘invisible’.

Figures

FIGURE 6. Pelecinobaccha invisibilis sp. nov. a – d. Holotype, female genitalia: a. 7 th tergite, dorsal. b. Apex, 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.