Pelecinobaccha alicia ( Curran, 1941 ) Curran, 1941

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 : 19-21

Pelecinobaccha alicia ( Curran, 1941) comb. nov.

Map 10. Figures 16 and 17 .

Baccha alicia Curran, 1941 .— Curran, 1941: 280. Type locality: Brazil, Santa Catarina, Nova Teutônia. Holotype female AMNH. Hull, 1949a: 140 (redescription), 195 (fig. 15, female abdomen), 214 (fig. 112, male abdomen).

Ocyptamus alicia . Thompson et al., 1976: 12 (catalog citation).

Baccha para Curran, 1941 .— Curran, 1941: 280. Type locality: Brazil, Santa Catarina, Nova Teutônia. Holotype female AMNH. Hull, 1949a: 163 (redescription), 194 (fig. 11, female abdomen), 214 (fig. 106, male abdomen), 216 (fig. 115, male abdomen), 262 (fig. 314, female wing, fig. 317 male wing). n. syn.

Ocyptamus para . Thompson et al., 1976: 24 (catalog citation).

Baccha sappho Hull, 1943 .— Hull, 1943a: 69. Type locality: Brazil, Santa Catarina, Nova Teutônia. Holotype female AMNH. Hull, 1949a: 170 (redescription), 224 (fig. 57, female abdomen), 262 (fig. 316, female wing). n. syn.

Ocyptamus sappho . Thompson et al., 1976: 26 (catalog citation).

Baccha vanda Hull, 1943 .— Hull, 1943d: 69. Type locality: Brazil, Santa Catarina, Nova Teutônia. Holotype male AMNH. Hull, 1949a: 174 (redescription), 214 (fig. 110, male abdomen), 222 (fig. 148, female abdomen), 262 (fig. 315, female wing). n. syn.

Ocyptamus vanda . Thompson et al., 1976: 29 (catalog citation).

Male. Head: Dark brown. Face pale on lateral 1/5. Lunule usually pale above antennal insertions, with central black maculae connected to the frontal triangle color by narrow dark vita. Frontal triangle entirely black to pale laterally except around eye contiguity, silvery-white pollen laterally continuous from face and might seem interrupted above antenna insertion. Vertical triangle with black pile forming a central single row; ocellar triangle separated by its length from posterior eye margin. Eye contiguity as long as vertical triangle length. Eye with subtriangular indentation on posterior margin at level of antenna insertion. Antennal insertions confluent, ventral margin with short dorsal extension; pile longer on scape. Dorsal ¼ of occiput with 2 rows of simple black pile, posterior row longer, middle ½ with 2–3 rows of pile, anterior rows mostly black pilose, some scale-like white pile ventrally, posterior row with longer, scale-like white pile; ventral ¼ with 3 irregular rows of scale-like white pile.

Thorax: Scutum dark brown, white-pollinose on pair of sub-median tapering vittae and an usually inconspicuous median vitta, notopleuron white-pollinose; mostly black pilose, except notopleuron white pilose anteriorly; scutum anterior row of white pile with shorter pile in the middle. Scutellum dark brown with mixed long and short black pile, subscutellar fringe pile long and black. Pleuron dark, sometimes with small pale area on posterior ½ of posterior anepisternum and dorso-posterior of katepisternum; pleuron mostly white pilose except black pilose dorso-posteriorly on the posterior anepisternum and on the anterior anepimeron. Plumula golden. Calypter white to yellow. Halter stem brown, capitulum light yellow to light orange.

Wing: Mainly dark, diffuse on posterior margin, entirely microtrichose; alula mostly hyaline with anterior margin darker, basally 1.5 times to apically 3.5 times as broad as c cell, entirely microtrichose

Legs: Proleg dark brown, apex of profemur and basal ½ of protibia sometimes pale to light brown. Mesoleg dark brown, apex of mesofemur and basal ½ of mesotibia sometimes yellow to light brown. Metaleg dark brown, yellow to light brown on basal ¼ of metatibia and from apex of metabasitarsomere until at least 3rd metatarsomere, 4th metatarsomere light brown, 5th metatarsomeres brown; metacoxa white pilose dorsally.

Abdomen: Dark brown to black; 3–3.5 times as long as thorax. First tergite black pilose latero-medially, white pilose elsewhere, sometimes mainly white pilose. Second tergite long, length 2.5–3.5 times minimum width, and entirely dark or with small median sub-lateral vittate/fasciate pale maculae; 2nd tergite with large rectangular region of dull black pollen medially that expands to lateral margin subapically, and mostly black pilose except white on base and baso-lateral ½, pile short and appressed dorsally and long and erect on base and laterally. Third tergite trapezoidal, length 2–2.5 times minimum width, sometimes pale on baso-lateral ⅔ and with a pair of vittate pale maculae medially, maculae sometimes inconspicuous (sub-shining); 3rd tergite with large triangular macula of dull black pollen medially, and with mostly appressed black pile, except white on baso-lateral ½. Fourth tergite subquadrate, slightly wider than long, sometimes with baso-lateral pale triangles; remaining characteristics as on 3rd. Fifth tergite either rectangular, wide and short or sub-quadrate, and entirely dark; 5th tergite dull black-pollinose medially but with pair of medial vittae of absence of pollen, and with appressed black pile; 3rd sternite dull blackpollinose on a medial spot. Genitalia: Cercus with 1–2 regular rows of pile on medial margin and 3 irregular rows on lateral margin. Surstylus short to slightly elongate, directed ventrally, with rounded apex, with strong setulae ventrally (around 12) sparse on apical ¼ or more concentrated on apical margin, with very little of the dorsal thin sclerotized layer, pilose on basal ½ of the dorsal surface. Subepandrial sclerite with lateral margin darker, short, quadrate, posterior margin concave, anterior lateral corners extended. Hypandrium mainly closed on ventral side. Distiphallus smooth and anterior surface straight. Postgonite with pile mainly on ventral surface, ventral surface expanded, straight, dorsal surface straight to slightly concave; postgonite apex convex anteriorly, with acute dorsal extremity, and rounded ventral extremity.

Female: Like male except: Sometimes more extensively pale on face. If frons with pale lateral margin, these end medially. Ocellar triangle 1.5–2 times its length from posterior eye margin and ~2 ocelli-width from lateral eye margin. Scutellum with mainly short black pile, subscutellar fringe usually with white pile medially; notopleuron. Pleuron sometimes pale on posterior ½ of posterior anepisternum and dorso-posterior region of katepisternum; dorso-posterior of posterior anepisternum and anterior anepimeron sometimes entirely white pilose, some specimens have a few black pile in these regions. Wing with subapical hyaline band (hyaline from apex of cell r1 to apex of cell dm), leaving a distinct apical dark spot. Legs usually with lighter regions than males. Second to 5th abdominal tergites with dull pollen restricted to a wide triangular medial region. Second tergite rectangular and long, but shorter than male (2–2.5 times as long as wide), entirely black or with medial fasciate pale maculae. Third tergite trapezoidal, shorter than on male. Fourth and 5th tergite with lateral margin mostly pale. Fifth tergite entirely black medially or with distinct medial vittate pale maculae. Sixth segment as long as or twice as long as 5th segment. Genitalia: 7th tergite normal but with anterior margin distinctly extended, apex rounded to acute, with a pair of lateral, weakly sclerotized, very long (as long as the 6th segment), narrow basal extensions into the 6th segment, extensions slightly expanded on basal ½; 7th segment lateral sclerite sub-triangular from a lateral view, narrow to large, anterior extremity blunt, posterior extremity acute; 7th sternite absent; 7th segment with central ventral longitudinal area bare. Eighth tergite with basal crest weakly sclerotized. Cercus enlarged and with 1 row of pile on inner ventral margin only.

Length. 6.5–10.5mm; wing 5–8.5 mm.

Distribution. Brazil (Minas Gerais, Paraná, Rio de Janeiro, São Paulo, Santa Catarina).

Material examined. BRAZIL. Minas Gerais, Tiradentes, hilltop nr. town Serra Tiradentes, 1200m, 16 Nov 1990, S. A. Marshall (1 ♀, DEBU); Paraná, Iguassú, Frank M. Hull Collection C.N.C. 1973, Dec 1941, Com. E. N. V. (2 ♀, CNC Diptera 161044 & 161096); Rio de Janeiro, Itatiaia, Maromba, Aug 1946, [M.P.] Barretto (1 ♀, MZUSP); Santa Catarina, Nova Teutônia, 27°11'S 52°23'W, 22 Feb 1936 (1 ♂, paratype Baccha vanda , CNC Diptera 161372); ..., nitidula [pink label], holotype vanda [red label], 10 Jun 1936, F. Plaumann (1 ♂, holotype Baccha vanda , AMNH); ..., Holotype sappho [red label], 6 Jul 1936, F. Plaumann (1 ♀, holotype Baccha sappho , AMNH); ..., 7 Feb 1937 (1 ♀, paratype Baccha vanda , CNC Diptera 161373); ..., 24 Feb 1937 (1 ♂, paratype Baccha vanda , CNC Diptera 161371); …, 6 Jul 1937 (1 ♀, paratype Baccha sappho , CNC Diptera 161377); ..., 28 Sep 1939 (1 ♂, allotype Baccha alicia , AMNH); ..., Holotype Baccha alicia Curran ♀ [red label] (1 ♀, holotype Baccha alicia , AMNH); ..., 15 Oct 1939 (1 ♂, paratype Baccha para , CNC Diptera 161379); ..., 18 Oct 1939 (1 ♀, paratype Baccha para , CNC Diptera 161380); ..., Baccha para Curran ♂ Allotype [red label], 28 Oct 1939 (1 ♂, allotype Baccha para , AMNH); …, Baccha para Curran ♀ Holotype [red label] (1 ♀, holotype Baccha para , AMNH); ..., Oct–Nov 1938–1939 (3 ♀, AMNH); ..., Mar 1948 (1 ♀, CNC Diptera 161045); ..., 300–500m, Aug– Feb 1952 –1971 (271 ♂, CNC Diptera 160885 –93, 160966 –92, 160866 –84, 160894 –965, 160993 – 161043, 161260 –71, 161272 –81 & MZUSP, 121 ♀, CNC Diptera 161046 –9, 161097, 161050 –95, 161098 –124, 161125 –7, 161251 –4, 161255 –6 & 161257 –9 & AMNH); São Paulo, Barueri, 12 Aug 1957, K. Lenko (1 ♂, MZUSP).

Comments. Curran (1941) stated that the females of Baccha alicia resembled B. para but differed in having a shorter and non-cylindrical 6th abdominal segment; the same character was used to separate these species in his key. “Non-cylindrical”, however, was an inaccurate characterization of the abdomen of this species, for what Curran saw was an artefact of preservation (as discussed in the Pelecinobaccha diagnosis). Some specimens we have examined fit Curran’s description, but the 6th segment varies from cylindrical to flattened. Furthermore, the female genitalia showed no difference between the cylindrical and the flattened condition. Curran (1941) described the third abdominal segment of B. alicia as having “the opaque part … usually partly or entirely divided by a pair of reddish vittae, which may be connected in front with large, lateral reddish triangles that extend to the middle of the segment laterally, the vittae sometimes absent and the lateral spots reduced[…]”. Similar variation is seen on the B. para specimens. The central vittae are either distinctly pale, sub-shining, or barely visible underneath the dull black pollinosity. In his description of B. para, Curran (1941) stated that “It is by no means certain that all of the males belong with the females and it is possible that some of them should be placed with [ Baccha ] alicia . However, there seems to be no good way to separate the males of these two species”. Since the slight differences are probably related to size, and that the condition of the fasciate maculae of the second segment varies considerably, it seems plausible that the difference observed by Curran between the females 6th segment is an intraspecific variation. Since all the specimens are sympatric and there is no obvious set of morphological characters that distinguishes the males either, B. para and B. alicia are here treated as synonyms. Since both species were simultaneously described we have followed the guidelines set out in article 24.2.1 of the International Code of Zoological Nomenclature (ICZN) to set one of these species, B. alicia , as the senior synonym.

When Hull (1943a) described B. sappho he compared it to Baccha para and noted that B. sappho had a shorter 6th abdominal segment. Hull did not mention B. alicia in his descriptions of B. sappho . Hull’s only distinction (the length of the 6th segment) for his species was the same as Curran’s for B. alicia .

Hull (1943d) described B. vanda , comparing it to B. para . We have examined both the types and Hull’s description, and conclude that there is insufficient evidence to treat B. vanda as a separate species. The facial coloration, scutum pollinosity and abdominal markings are a mixture of preservation artefact and intraspecific variation.

P. alicia has two common forms, a medium-sized and a small form ( para variation), which usually differ as follows:

Medium sized flies (~ 10mm): The males have a slightly longer, rectangular surstylus with sparse setulae on ventro-apical ¼. The females have the 6th segment as long as the 5th, the 7th tergite with a rounded apex, and a triangular and narrow 7th segment lateral sclerite.

Small flies (6–8mm, not counting the 6th segment): The males have a shorter and sub-quadrate surstylus with setulae concentrated on the ventro-apical margin. The females usually have central pairs of pale vittae on the 3rd–5th abdominal tergites, although sometimes the vittae are very weak, the 6th segment very long (2 times as long as the 5th), the 7th tergite with acute apex and a triangular and wide 7th segment lateral sclerite.

Other males of this species (CNC Diptera 161268 –9) have a slightly elongate epandrium, with an apically directed, slightly lanceolate surstylus. These males also have a white subscutellar fringe, mainly white pile anterior to the transverse suture on the notopleuron, on the posterior anepisternum and on the anterior anepimeron, and apical ¼ to 1/5 of the metabasitarsomere pale. White pile in these regions is common among males and females of this species, although not so predominant as in this variation.

Figures

FIGURE 16. Pelecinobaccha alicia (Curan, 1941), female. a. Head, dorsal. Detail: Dorsal occiput. b. Wing. c. Abdomen, apex, dorsal, variation. d – h. Genitalia: d. 6 th and 7 th segments, dorsal, variation. e. 6 th and 7 th segments, dorsal. f. Apex, dorsal. g. Apex, lateral, variation. h. 7 th segment, lateral. i. Holotype, habitus, dorsal. 5 sg: 5 th segment, 6 sg: 6 th segment, 7 tg: 7 th tergite, 8 tg: 8 th tergite, 10 tg: 10 th tergite, b ap: basal apodeme of the 7 th tergite, cerc: cercus.

FIGURE 17. Pelecinobaccha alicia (Curran, 1941), male. a – b. Abdomen: a. Oblique dorsal. b. Oblique dorsal, variation. c – f. Genitalia: c. Epandrium, lateral, variation. d. Surstylus, ventral. e. Hypandrium, lateral. f. Hypandrium, ventral.