Pelecinobaccha nubilorum

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 : 57-59

Pelecinobaccha nubilorum Miranda & Thompson sp. nov.

Map 13. Figure 35 .

Type locality. Costa Rica, San José, Llano Bonito, 4.4 Km SO. del Cerro Ventisquero, 2450m, 9°27'N 83°32'W. Holotype female INBio.

Male. Head: Black. Face with black pile laterally on dorsal ½. Lunule pale above antennal insertion, central maculae broadly connecting to frons color. Frontal triangle with white-silver pollen restricted to ventral ½ laterally, continuous from face but ventral pollen oriented ventro-dorsally, brown-pollinose medially. Vertical triangle with 3 rows of pile, but most pile concentrated in a single median row; ocellar triangle separated by its length from posterior eye margin. Eye contiguity as long as vertical triangle length. Eye with posterior indentation at level antennal insertion. Antennal insertions separated. Occiput with dull dark pollen on dorsal ⅓, otherwise occiput covered with white pollen; dorsal ¼ of occiput with 2 rows of simple black pile, anterior row shorter; middle ½ with posterior row of long scale-like white pile, and 1–2 anterior rows of shorter, simple black pile, sometimes scale-like and white ventrally; ventral ¼ with 2–3 irregular rows of scale-like white pile

Thorax: Scutum black, mostly brown dull pollinose, covered by except with sparse white pollen on notopleuron, and with a pair of sub-median vittae of concentrated dull pollen, and sometimes a median narrow vita, visible from a posterior angle; scutum black pilose, longer on notopleuron, and with anterior row of shining white pile with shorter pile medially. Scutellum black, with metallic-shining pollen, with long black pile, subscutellar fringe pile long and white. Pleuron black; white pilose, with some black pile on dorso-posterior of posterior anepisternum and anterior anepimeron. Plumula long and white to yellow. Calypter yellow, margin and pile brown. Halter brown, capitulum yellow to orange.

Wing: Infuscated with dark brown anterior margin (dark brown on cells bc, c, sc, r, r1, r2+3, except middle of posterior margin, and most of bm), entirely microtrichose; alula hyaline with anterior margin infuscated, narrow, basally 2 times to apically 3 times as broad as c cell, entirely microtrichose.

Legs: Proleg black, profemur apical 1/6 and base of protibia pale. Mesoleg black, apex of mesofemur and base of mesotibia pale, basal ½ of mesotibia pale, mesobasitarsomere pale to light brown; mesobasitarsomere dorsal pile black on base to basal ½. Metaleg black, pale on apex of metafemur, base of metatibia and apex of the metabasitarsomere until the 3rd metatarsomeres; metacoxa white pilose.

Abdomen: Black; ~3 times as long as thorax. First tergite mainly white pilose on baso-ventral ½ and basodorsally, otherwise pile black. Second tergite long, length ~3.5 times minimum width, with median sub-lateral pair of vittate pale maculae; 2nd tergite with median black dull pollinose rectangular region, and mainly with appressed,except erect basally and laterally, and black pile, except white basally and on baso-lateral ½. Third tergite trapezoidal and long, length ~3 times minimum width, pale on baso-lateral ½ connected basally to pair of median short pale vittae; 3rd tergite largely dull black-pollinose medially, and with mainly appressed and black pile, except erect and white on baso-lateral ½; 3rd sternite rectangular and long. Fourth tergite rectangular and long, slightly longer than wide, pale on baso-lateral corners connected basally to median pair of pale vittae; 4th tergite dull black-pollinose on median triangular region, and mainly with appressed and black pile, except erect and white on baso-lateral ⅓. Fifth tergite rectangular and wide, pale on baso-lateral corners, with median pair of pale vittae; 5th tergite with 3 vittae of dull black pollen between the pale vittae, the pollinose vittae sometimes fused, and with appressed black pile. Pale regions sometimes faint on abdominal segments. Genitalia: Cercus with 1 row of pile on medial margin and 3 rows on lateral margin. Surstylus rectangular in lateral view, directed apicoventrally, with weak setulae ventrally (around 24), shorter on apical ¼ and base (around 21) and longer on the middle (around 3), sparse pilose on baso-dorsal ⅔. Subepandrial sclerite sub-quadrate, apex trapezoidal, posterior margin with trapezoidal notch, anterior margin slightly concave, homogenously sclerotized. Hypandrium with ventral notch on anterior ⅔. Phallapodeme well sclerotized throughout. Distiphallus with anterior surface straight. Postgonite with lateral surface expanded ventrally on basal ½, ventral and dorsal surfaces concave; postgonite apex ventral extremity rounded and large, extended ventro-apically, dorsal extremity acute and directed basally.

Female (found at altitudes <1700 m.): Similar to male except: Face slightly lightened on ventro-lateral ⅓. Frons with white-silver pollen continuous from face and restricted to lateral margin until ventral ⅔. Ocellar triangle ~2 times its length from posterior eye margin and ~1 ocellus-width from lateral eye margin. Occiput dull darkpollinose on dorsal 1/5; anterior row of dorsal occiput very short, anterior rows of middle ½ of occiput with simple black pile restricted dorsally. Scutum covered with white pollen on notopleuron, with a pair of sub-median tapering vitta and an inconspicuous postero-anterior narrow median vittae of white pollen; scutum with continuous anterior row of shining white pile. Scutellum dorsal pile shorter. Plumula brown. Calypter gray, margin and pile darker. Wing mostly hyaline with anterior margin dark brown (except r2+3 middle until apex of posterior margin hyaline); alula hyaline, basally 1.4 times to apically 3.2 times as broad as c cell. Pro and mesoleg dark brown. Profemur with apical ½ gradually becoming pale, protibia with basal ½ pale, 2nd to 4th protarsomeres slightly enlarged. Apex of mesofemur and basal ½ of mesotibia pale, 2nd to 4th mesotarsomeres slightly enlarged, black pile on dorsal base of mesobasitarsomeres not so distinct. Apical ⅓ to ¼ of the metabasitarsomere to 4th metatarsomeres pale, apical metatarsomere slightly darker; with some white pile dorsally on metacoxa. Abdomen ~3.5 times as long as thorax. First tergite mainly black pilose, pile white baso-ventrally and dorsally. Second tergite long, slightly constricted medially, length ~2.5 times minimum width, with median-lateral pale triangular maculae and median black dull pollinose triangular region; 2nd tergite mainly with black appressed pile, except white and erect basally and on basolateral ½. Third tergite trapezoidal and short, as long as narrowest width, with pair of baso-lateral arcuate pale maculae connected basally to median pair of short pale vittae, and with erect and white pile baso-laterally; 3rd sternite normal. Fourth tergite rectangular and wide, entirely dark, with appressed black pile. Fifth tergite rectangular and wide, entirely dark, remaining characteristics as on male 4th tergite. Sixth segment long, ~1.5 times as long as 5th. Genitalia: Strongly sclerotized. Seventh tergite with extended apical margin, longer than on other form, basal extensions slightly shorter than 6th segment; 7th segment lateral sclerite sub-rectangular, acute basoventral extensions very short. Eighth segment longer than on other form; 8th tergite entirely sclerotized, with basal and apical notches, basal crest short; 8th sternite unsclerotized medially.

Female (found at altitudes> 2300 m.): Similar to male except: Black pile of face restricted ventrally to frontal prominence. Frons with white-silver pollen continuous from face and restricted to lateral margin until ventral ⅔; ocellar triangle ~2 times its length from posterior eye margin and ~1 ocellus-width from lateral eye margin. Occiput dull dark-pollinose on dorsal 1/5; anterior row of dorsal occiput very short, anterior rows of middle ½ of occiput with simple black pile restricted dorsally. Scutum covered with white pollen on notopleuron, with a pair of sub-median tapering vitta and an inconspicuous postero-anterior narrow median vittae of white pollen; pile white on notopleuron but sometimes with a few black pile immediately anterior to transverse suture. Scutellum dorsal pile shorter. Pleuron entirely white pilose. Calypter white. Wing mostly hyaline with anterior margin dark brown; alula hyaline, narrow, basally as wide as to apically 2.5 times as broad as c cell. Pro and mesoleg dark brown. Profemur with apical ½ gradually becoming pale, protibia with basal ½ pale, probasitarsomeres brown, 2nd to 4th protarsomeres slightly enlarged and black. Apex of mesofemur and basal ⅔ of mesotibia pale, middle of mesotibia sometimes light brown, 2nd to 4th mesotarsomeres slightly enlarged and black; mesobasitarsomere entirely white pilose dorsally. Basal ½ of metafemur pale, basal ¼ of metatibia pale. Abdomen ~3.5 times as long as thorax. First tergite usually with fewer black pile. Second tergite length ~3.5 times minimum width, pale maculae sometimes absent, with median black dull pollinose triangular region; 2nd tergite mainly with appressed and black pile, except erect and white on basbasally and on baso-lateral ⅔. Third tergite length ~2 times minimum width; 3rd sternite unmodified. Sixth segment as long as 5th. Genitalia: Similar to the other form except 7th tergite with shorter apical margin and shorter 8th segment.

Length. 11.5–13mm; wing ~ 9mm.

Distribution. Costa Rica (Limón, Puntarenas, San José), Mexico (Guerrero).

Primary type. Holotype: Female in good condition. Left proleg and genitalia dissected and placed in individual plastic tubes pinned with the specimen. Holotype labels: ‘ COSTA RICA, Prov. San José, // Llano Bonito, 4.4 Km SO. del Cerro // Ventisquero. 2450m. 4 MAY 1997. // A. Picado. L_S_378500_513200 // #46215’ ‘INBIO CRI002 504351’ ‘ Holotype // Pelecinobaccha // nubilorum // Miranda’ [red label].

Paratypes. COSTA RICA. Limón, P. Int. La Amistad, Send. a Cerro Hoffman, 2460m., Libre, L S 340258 577465, #73656, 24 Mar 2003, M. Alfaro (1 ♀, INB0003713242 INBIOCRI COSTA RICA); ..., Send. el Alto, 2500m., Libre, L S 340258 577465, #74177, 26 Jun 2003, M. Alfaro & R. Delgado (1 ♀, INB0003724521 INBIOCRI COSTA RICA); Puntarenas, Monteverde, Cerro Chomogo, 1800m., 22–30 Aug 1996, M. Wood (1 ♂, CNC Diptera 161223); ..., Sendero a Cerro Echandi, primer Campamento borde de Tacotal, 900m., Red Mariposera, L_S_326500_591700, #50838, 12–14 Apr 1998, M. Moraga (1 ♂, INB0003088849 INBIOCRI COSTA RICA); San José, Est. Cuereci, Sendero El Carbón, 5 Km al E. de Villa Mills, 2700m., L_S_390100_500100, #7685, 0 1 Jun 1996, A. Picado (1 ♀, INBIO CRI002 452318); ..., Est. Santa Elena, Las Nubes, 1210m., L_S_371750_507800, #7888, 5–21 Jul 1996, M. Segura (2 ♀, INBIO CRI002 469634 & 469711); ..., Send. La Bota, 3.5 Km al SE. del Cerro Chucuyo, 1690m., L_S_373400_507300, #7891, 18–22 Jul 1996, M. Segura (1 ♀, INBIO CRI002 446931); ..., San Gerardo de Dota, Albergue Savegre, Send. Los Robles, 2300–2450m., L_S_389000_484200, #49970, 20–22 Jan 1998, M. A. Zumbado (1 ♀, INBIO CRI002 415918); ..., Santa Ana, Zona Prot Cerro de Escazú, Bebedero, Alto Tapezco, 1760m., Rede con agua miel, L N 209000 518900, # 52373, 14 Jan 1999, M. A. Zumbado (1 ♂, INB0003034654 INBIOCRI COSTA RICA). MEXICO. [Guerrero], Gro 10Km S Filo de Caballos, 2700 m., 14 Jul 1992, D. M. Wood (1 ♀, CNC Diptera 161224).

Comments. Female specimens of this species from altitudes below 1700m have a shorter 3rd abdominal segment and longer 6th segment than those from altitudes above 2300m, besides the other small variations described above. We have seen no specimens of this species from altitudes between 1700m and 2300m. F.C. Thompson’s ‘ Ocyptamus CR-41b’ keys out to this species.

Etymology. The specific epithet refers to ‘clouds’, an allusion to the high elevations where the specimens were collected (which is also the name of one the localities where they were collected, Las Nubes = The clouds). It is to be treated as a noun in the genitive case.

Figures

FIGURE 35. Pelecinobaccha nubilorum sp. nov. a – d. Female genitalia: a. 7 th tergite, dorsal. b. Apex, dorsal. c. 7 th segment, lateral. d. Apex, lateral. e – h. Male genitalia: e. Surstylus, lateral. f. Surstylus, 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.