Pelecinobaccha mexicana ( Curran, 1930 ) Curran, 1930

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 : 54-55

Pelecinobaccha mexicana ( Curran, 1930) comb. nov.

Map 12. Figure 33 .

Baccha mexicanus Curran, 1930 .— Curran, 1930: 6 (nom. nov. for lugubris Williston ). Hull, 1949a: 216 (fig. 114, male abdomen), 254 (fig. 360, male wing).

Baccha lugubris Williston, 1891 .— Williston, 1891: 37 (preocc. Phillipi, 1865). Type locality: Mexico, Tabasco, Venta de Zopilote, 2800 ft., Teapa; Guerrero, Chilpancingo, 4600 ft., Veracruz, Atoyac. Holotype male BM NH (not examined) and female AMNH (synonymised by Fluke 1956).

Baccha batesi Curran, 1939 .— Curran, 1939: 10. Type locality: Guatemala, San Sebatian, Reu. Holotype male AMNH. Hull, 1949a: 220 (fig. 136, female abdomen), 282 (fig. 382, female wing) (synonymised by Thompson et al. 1976).

Male. Head: Black. Face pale on lateral ⅓ to ¼. Lunule usually pale dorsal to antennal insertions, central black macula connected to frontal triangle color by median vitta. Frontal triangle entirely black, with silvery-white pollen laterally, continuous from the face, and brown pollen medially. 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 sub-triangular indentation on posterior margin at level of antenna insertion. Antennal insertions confluent, ventral margin with short dorsal extension. Dorsal ¼ of occiput with 2 rows of simple black pile, anterior row with very short pile, middle 2⁄4 with 3–4 rows of scale-like white pile, posterior row with very long pile, anterior rows shorter and sometimes with some simple black pile dorsal to indentation, ventral ¼ with 2–3 rows of scale-like white pile.

Thorax: Scutum black, mostly brown dull pollinose, except white on notopleuron, with sub-median short pair of vittae of concentrated dull pollen; scutum mainly black pilose, except white on notopleuron and anterior to scutellum, and usually with some black pile anterior to transverse suture on notopleuron; scutum anterior row of shining white pile with shorter pile medially. Scutellum dark brown to black, with shining brown pollen, pile long and black, longer than on scutum, sub-scutellar fringe long and white. Pleuron white pilose and black, except usually pale on posterior ½ of posterior anepisternum and dorso-posterior katepisternum. Plumula long and white. Calypter white. Halter yellow to light brown, capitulum sometimes orange.

Wing: Dark brown, posterior margin lighter (dark on cells bc, c, sc, r, r1, r2+3 and bm, other cells gradually get lighter towards the posterior margin), entirely microtrichose; alula infuscated, sometimes slightly brown on anterior margin, large, basally 1.4 times to apically 3.4 times as broad as c cell, entirely microtrichose.

Legs: Proleg brown to dark brown, profemur and base of protibia pale. Mesoleg light brown to dark brown, apex of mesofemur and basal ⅔ of mesotibia pale. Metaleg dark brown, pale on basal ½ of metafemur, base of metatibia and apical ¼ to 1/5 of metabasitarsomere until 5th metatarsomere, 5th metatarsomere sometimes light brown; white pilose dorsally on metacoxa.

Abdomen: Dark brown to black, 3.9 times as long as thorax. First tergite black pilose median-laterally, white elsewhere. Second tergite long, length 4 times minimum width, usually pale on baso-lateral ⅔; 2nd tergite with rectangular black dull pollinose region medially, and mainly black pilose, except white basally and on baso-lateral ⅔, pile long laterally and mostly appressed, except erect basally and laterally. Third tergite trapezoidal and long, length 2.8 times minimum width, usually pale on baso-lateral ½ and on apical margin; 3rd tergite with large central triangular region of dull black pollen, and with appressed black pile, except erect and white on baso-lateral corners; 3rd sternite rectangular and long. Fourth tergite sub-quadrate long, 1.2 times as long as wide, with baso-lateral triangular pale maculae, and with with appressed black pile, except white on baso-lateral corners; remaining characteristics as on 3rd. Fifth tergite rectangular and wide, sometimes pale on baso-lateral corners, with 3 central vittae of dull black pollen, and with appressed black pile. Genitalia: Cercus with 2 irregular rows of pile on medial margin, 3 irregular rows of pile on lateral margin. Surstylus long with rounded apex in lateral view, directed ventrally, with setulae ventrally, short on apical ¼ (around 10) and slightly longer medially and basally (around 3 on each region), pilose on basal ½ dorsally. Subepandrial sclerite homogenously sclerotized, rectangular and long, slightly concave on posterior margin, trapezoidal apically, with a pair of short extensions on apex. Hypandrium with ventral notch on anterior ½, notch with straight posterior margin. Phallapodeme well sclerotized dorsally, lighter ventrally. Basiphallus with posterior extremity long; distiphallus with medial convexity on anterior surface, apex curved apically. Postgonite with ventral surface straight, dorsal surface concave; postgonite apex convex anteriorly and rounded on ventral extremity and acute on dorsal extremity.

Female: Like male except: Frons normal; lateral white pollen restricted to ventral ¾ of frons. Vertex narrow; ocellar triangle ~2.5 times its length from posterior eye margin and ~1 occellus-width from lateral eye margin. Wing dark regions more sharply defined (dark brown on cells bc, c, sc, r, r1, r2+3 except for hyaline middle portion on posterior margin, base of r4+5 and bm, light brown on basal ½ of dm, apical ⅓ of cu p and basal ¾ of cua1, other cells hyaline). Profemur sometimes entirely pale, protibia sometimes with basal ⅔ pale. Second to 4th protarsomeres and 3rd and 4th mesotarsomeres slightly swollen. Metabasitarsomere sometimes with apical ⅓ pale. First abdominal tergite with less black pile. Second abdominal tergite shorter, length 2.9 times minimum width, pale on baso-lateral ½, and with central triangular region of dull black pollen. Third abdominal tergite shorter, length 1.7 times minimum width, with baso-lateral pale triangles. Fourth abdominal tergite rectangular and wide, sometimes with baso-lateral fasciate pale maculae. Sixth segment conical, normal, 1.2 times as long as 5th tergite. Genitalia: 7th tergite rectangular with triangular apex; 7th segment lateral sclerite rectangular, with baso-ventral extensions. Eighth tergite unsclerotized medially, basal crest normal, with subapical sclerotized bridge joining both halves, apex unsclerotized on dorsal and apical margin; 8th sternite unsclerotized medially. Cercus with 1 row of pile on apical margin.

Length. 11–14mm; wing 8.5–11mm.

Distribution. Costa Rica (Guanacaste, Limón), El Salvador (La Libertad), Guatemala (Alta Verapaz, Chilmatenango), Mexico (Chiapas, Guererros, Morelos).

Material examined. COSTA RICA. Guanacaste, R.V.S. Bosque Diriá, Libre, 160m., L N 239623 361899, #73746, 13 Feb 2003, Y. Cardenas (1 ♂, INB0003717520 INBIOCRI COSTA RICA); ..., Río Boston, 300m., L_N_253350_435900, #47847, 21 Jun 1997, F. Alvarado (2 ♂, INBIO CRI 002 572690 & 572691); ..., Santa Cruz, Vista del Mar, Torre COCESNA, Red. com aguamiel, 972m., L N 235350 357500, #73744, 10 Feb 2003, Y. Cardenas (1 ♂, INB0003717457 INBIOCRI COSTA RICA, 1 ♀, INB0003717459 INBIOCRI COSTA RICA); ..., Manual (red. libre), L N 235340 357490, #56433, 16 Feb 2000, Y. Cardenas (1 ♀, INB0003077657); Limón, R. B. Hitoy Cerere, Send. Espavel, 560m., Libre, L S 401200 569800, #73453, 12–30 Mar 2003, F. Rojas, B. Gamboa & W. Arana (1 ♀, INB0003706638 INBIOCRI COSTA RICA). EL SALVADOR. [La Libertad], Santa Tecla, 0 6 Jun 1958, L. Bottimer (1 ♀, USNM ENT 00257759). GUATEMALA. [Alta Verapaz], S. Cristobal, Santa Vera Paz, 17 May 1926, J. M. Aldrich (1 ♂, USNM ENT 00257758); [Chimaltenango], Yepocapa, Aug 1949, H. T. Dalmat (1 ♂, USNM ENT 00257757); ..., Finca Recreo, 0 1 Sep 1949, O. Ochoa (1 ♀, USNM ENT 00257752). MEXICO. Chiapas, 6.0 km SW Ocosingo, 1400m, 22 Sep 1992, M. Wood (1 ♀, CNC Diptera 161326); ..., 15km. N Ocosingo, 20 May 1981, C.M. & O.S. Flint, Jr. (1 ♂, USNM ENT 00257751); …, El Sumidero, 14 Sep 1974, G. Bohart & W. Hanson (1 ♂, USNM ENT 00257651); …, Finca Prussia (33 km S. Jaltenango), 1000m., 10–12 May 1985, A. Freidberg (1 ♂, USNM ENT 0 0 257753, 2 ♀, USNM ENT 00257754–5); Guerrero, Iguala, 33 Mi S, 1450’, 5 Aug 1954, J. G. Chillcott (1 ♂, CNC Diptera 161324); Morelos, Cuernovaca, 14 Mi S, 3200’, 3 Aug 1954, J. G. Chillcott (1 ♂, CNC Diptera 161322); ..., 35 Mi. S., Frank M. Hull Collection C.N.C. 1981, 27 Aug [19]59, R.H. Painter & E.M. Painter (1 ♂, CNC Diptera 161325).

Figures

FIGURE 33. Pelecinobaccha mexicana (Curran, 1930). a – b. Female genitalia: a. Dorsal. b. Lateral. c – f. Male genitalia: c. Epandrium, lateral. d. Epandrium, ventral. e. Hypandrium, lateral. f. Hypandrium, ventral. g. Holotype, habitus, dorsal (copyright AMNH). 7 tg: 7 th tergite, 8 tg: 8 th tergite, 10 tg: 10 th tergite, cerc: cercus, s scl: subepandrial sclerite.