Relictanum nero ( Curran, 1939 ) Curran, 1939

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 : 94-96

Relictanum nero ( Curran, 1939) comb. nov.

Map 2. Figure 47 .

Baccha nero Curran, 1939 .— Curran, 1939: 8. Type locality: Guyana, Kaieteur. Holotype male BMNH (not examined).

Ocyptamus nero . Thompson et al., 1976: 23 (catalog citation).

Baccha infanta Hull, 1943 .— Hull, 1943a: 74. Type locality: Colombia. Holotype male CNC. Hull, 1949a: 159 (redescription), 224 (fig. 151, abdomen). n.syn.

Ocyptamus infanta . Thompson et al., 1976: 21 (catalog citation).

Baccha triloba Hull, 1944 .— Hull, 1944a: 7. Type locality: “Amazon”. Holotype female BMNH. Hull, 1949a: 172 (redescription), 224 (fig. 153, abdomen), 258 (fig. 298, wing). n. syn.

Ocyptamus trilobus . Thompson et al., 1976: 28 (catalog citation).

Baccha philodice Hull, 1950 .— Hull, 1950: 227. Type locality: Peru, Chanchamayo. Holotype female CNC. n. syn.

Ocyptamus philodice . Thompson et al., 1976: 25 (catalog citation).

Male. Head: Black. Face narrow, almost straight dorsal to tubercle, pile white, black ventral to antennal base; gena black. Lunule entirely black. Frontal triangle entirely black, dull brown-pollinose medially and sometimes divided medially by narrow bare vitta, white-silver pollen continuous from face restricted to lateral margin except around eye contiguity, black pilose; frontal prominence slightly protuberant at level of frontal triangle. Vertical triangle with 1 median row of pile; ocellar triangle separated by less than its length from posterior eye margin and adjacent to the lateral eye margin. Eye contiguity 1.5 times as long as vertical triangle shorter length. Eye with posterior indentation at level of antennal insertion. Antennal insertions confluent. Antennae close together. Dorsal ¼ of occiput with dull brown pollen, ventral ¾ with white-silver pollen; dorsal ¼ with 1 row of simple white or black pile; middle ½ with 2 rows of white scale-like pile, posterior row longer, with some simple black pile on anterior row; ventral ¼ with 1–2 rows of scale-like white pile posteriorly, anterior region bare.

Thorax: Scutum black, with sub-median antero-postero pair of dull brown-pollinose vittae; scutum mainly black pilose except for the anterior row of longer, shining, white pile, slightly interrupted in the middle. Scutellum black, with sparse short black pile, subscutellar fringe pile normal and black. Pleuron black and pile white, except sometimes with a few black pile dorsally on posterior ½ of posterior anepisternum. Plumula short and gray. Calypter white to gray with black margin. Halter white to light orange.

Wing: Entirely light brown, entirely microtrichose; alula light brown, linear, mainly 2.3 times as broad as c cell, entirely microtrichose.

Legs: Proleg black, protibia sometimes with basal ⅓ pale. Mesoleg black, apex of mesofemur and basal ⅓ of mesotibia sometimes pale. Metaleg black, apex of metafemur and basal ¼ of metatibia sometimes pale; metacoxa pile mainly white.

Abdomen: Black; about 3 times as long as thorax. First tergite with white pile ventrally, otherwise pile black; pile longer laterally. Second tergite long, length 3.5 times minimum width, and with subapical fascia of dull black pollen; 2nd tergite mainly with appressed and black pile, except erect laterally, and white on baso-lateral ½. Third tergite trapezoidal, length 2 times minimum width, and with large triangular macula of dull black pollen medially; 3rd tergite with mainly appressed and black pile but with distinct shining white pile intermixed, visible from a dorso-anterior angle, pile slightly longer and erect on baso-lateral corners; 3rd sternite much narrower than tergite. Fourth tergite sub-quadrate, with pair of sub-median sub-shining vittae apically; remaining characters as on 3rd. Fifth tergite rectangular and wide, dull pollinose region divided into 3 median vittae; remaining characteristics as on 4th. Genitalia: Cercus with 1–2 regular rows of pile on medial margin and 3 irregular rows on lateral margin. Surstylus quadrate in lateral view, with acute apical extremity and subapical dorsal convexity, directed ventrally, with weak setulae (around 20) throughout the ventral side but concentrated on ventro-apical margin, with very few pile on dorsal surface. Subepandrial sclerite rectangular, with slightly extended basal corners. Hypandrium slightly rounded, with trapezoidal ventral notch extending to anterior ½, basal notch margin rounded, with a few long pile (around 6) subapically on ventro-lateral margin. Phallapodeme narrow. Basiphallus with posterior extremity long and curved towards base of hypandrium, distiphallus smooth and anterior surface slightly curved posteriorly. Postgonite narrow, with few pile on ventral ⅓, ventral surface twice undulated, dorsal surface concave; postgonite apex rounded and with subapical lateral spine.

Female: Like male except: Slightly larger than males. Face pile entirely white; pile white around frontal prominence; frons narrow. Vertex very narrow, ocellar triangle ~1.5 times its length from posterior eye margin and adjacent to lateral eye margin. Scutum pollinose vittae white, notopleuron with sparse white pollen; all pile white on scutum, scutellum and pleuron. Wing entirely dark, but lighter than male. Basal ⅓ of protibia, basal ½ of mesotibia and basal ⅓ of metatibia pale. First tergite entirely white pilose. Third tergite sometimes with pair of submedian sub-shining vittae; 3rd sternite similar to tergite. Fourth tergite rectangular and wide. Sixth tergite 2 times shorter than 5th tergite. Genitalia: 7th tergite rectangular, normal, with pile only on apical ¼; 7th sternite absent, membranous region area greater than the 7th tergite. Eighth tergite notched anteriorly; 8th sternite present. Tenth tergite notched anteriorly and with a straight posterior margin; 10th sternite reduced to triangular sclerite. Cercus basally fused by narrow strip to lateral margin of 10th tergite, densely pilose and with setulae directed basally on dorsal ½.

Length. 5–7mm; wing 4–5.5mm.

Distribution. Bolivia (Beni, La paz), Brazil (Goiás), Colombia (Boyaca), French Guiana, Mexico (Chiapas), Peru (Cuzco, Huanuco, Junín, Madre de Dios).

Material examined. UNKNOWN. Amazon, 66-53, Holotype [circular white label with a red margin], Holotype Baccha triloba Hull [red label] (1 ♀, holotype Baccha triloba , BMNH). BOLIVIA. Beni, 20 km W Laranjeiras, 3–5 Aug 1964, J. K. Bouseman & J. Lussenhop (1 ♂, AMNH); La Paz, Alto Río Beni, south of Río Inicua, 1100m, 15–18 Jan 1976, L. E. Peña (2 ♂, 1 ♀, AMNH). BRAZIL. Goiás, Jataí, Faz. Nova Orlandia, Jan 1964, Martins, Morgante & Silva (1 ♂, MZUSP). COLOMBIA. Boyaca, Muzo, 900m, Holotype infanta [red label], Holotype Baccha infanta Hull CNC No 20518 [red label], 1936, J. Bequaert (2 ♂, holotype Baccha infanta , two specimens on the same pin, CNC). FRENCH GUIANA. 3.5 km N Saül, 3°38–40'N 53°13'W, 160–260m, tropic forest, 4–12 Oct 1995, D. Grimaldi (1 ♂, AMNH). MEXICO. Chiapas, Finca Prusia (33 km S. Jaltenango), 1000m, 10–12 May 1985, A. Freidberg (1 ♂, USNM ENT 00257659). PERU. Cuzco, Pau–Cartambo, Puente San Pedro (50 km NW Pilcopata), 1600m, 3 Sep 1988, A. Freidberg (1 ♂, USNM ENT 0 0 257657, 1 ♀, USNM ENT 00257656); ..., Quincemil, 13–31 Aug & 24–31 Oct 1962, [L.] Pena (1 ♂, CNC Diptera 161182, 1 ♀, CNC Diptera 161184); Huanuco, Rio Monzon, W of Tingo Maria, 20 Jun 1964, R. M. Straw (1 ♂, USNM ENT 00257654); Junín, Chanchamayo, 1100m, Holotype Baccha philodice Hull [red label], Holotype Baccha philodice Hull CNC No 20526 [red label], 16 Aug [19]48, J. Schunke (1 ♀, holotype Baccha philodice , CNC Diptera 188816); ..., Paratype Baccha philodice Hull [yellow label], 8 Aug [19]48, J. Schunke (1 ♀, paratype Baccha philodice , CNC Diptera 188817); ..., La Merced, 1000m, FS574, Boyes Cytolog. Coll. FS574 To remain in the C.N.C. [yellow label], 2 Dec 1970, J.W. Boyes (1 ♂, CNC Diptera 161183); Madre de Dios, Manu, Rio Manu, Pakitza, 250m, 12°7'S 70°58'W, 9–23 Sep 1988, A. Freidberg (1 ♂, USNM ENT 0 0 257655, 1 ♀, USNM ENT 00257670); ..., Erika (near Salvacion), 550m, 5–6 Sep 1988, A. Freidberg (1 ♂, USNM ENT 00257658); ..., nr. Pakitza, 12°17' S 70°57' W, 250m., 9 Sep 1988, W. N. Mathis (1 ♀, USNM ENT 00257671).

Comments. There are two males on the pin of the holotype of B. infanta , but in Hull’s (1949) holotype abdominal drawing (fig. 151), it is clear that the holotype he was referring to is the specimen on the left, with the better preserved abdomen, which is hereby fixed by monotypy (ICZN 73.1.2 and 72.4.1.1).

The holotype of B. nero fits this redescription perfectly, based on information provided by Nigel Wyatt ( Diptera curator at the BMNH). The female holotype of B. triloba has the same characters as the male holotype of B. infanta , with the exception of sexual dimorphism (e.g. vertex and frons width). Hull apparently failed to notice that both B. infanta and B. philodice have a pale region on the metatibia, which Hull thought was present only in B. philodice .

Figures

FIGURE 47. Relictanum nero (Curran, 1939). a – b. Female genitalia: a. Dorsal. b. Lateral. c – f. Male genitalia: c. Surstylus, ventral. d. Epandrium, ventral. e. Hypandrium, lateral. f. Hypandrium, ventral. g. Female, habitus, dorsal. 8 tg: 8 th tergite, 10 tg: 10 th tergite, cerc: cercus, s scl: subepandrial sclerite.