Relictanum crassum Walker 1852, comb. nov.
Creators: name: Miranda, Gil Felipe Gonçalves
name: Marshall, Stephen A.
name: Skevington, Jeffrey H.
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Syrphidae
Relictanum
Relictanum crassum

description: Relictanum crassum (Walker, 1852) comb. nov.
Map 3. Figure 44.
Baccha crassa Walker, 1852. Walker, 1852: 222. Type locality: Brazil. Holotype male BMNH (not examined).
Ocyptamus crassus. Thompson et al., 1976: 15 (catalog citation).
Baccha zeteki Curran, 1930. Curran, 1930: 8. Type locality: Panama, Canal Zone, Barro Colorado Island. Holotype male AMNH. Hull, 1949a: 175 (redescription), 204 (fig. 66, female abdomen). n.syn.
Ocyptamus zeteki. Thompson et al., 1976: 30 (catalog citation).
Male. Head: Black. Lunule sometimes weakly pale dorsal to antennal insertions. Frontal triangle brown dull pollinose, with pair of median oval spots of silvery-white pollen laterally, pollen sparse centrally, only frontal prominence protuberant. Vertical triangle with 1 median row of pile; ocellar triangle ~1.5 times its length from posterior eye margin. Eye contiguity slightly shorter than vertical triangle length. Eye with posterior indentation slightly ventral to antennal insertions. Antennal insertions confluent. Dorsal ¼ of occiput with 1 row of simple black pile; middle ½ with 2–3 rows of scale-like white pile, posterior row longer, anterior rows sometimes with a few simple black pile dorsally; ventral ¼ with 2–3 irregular rows of scale-like white pile.
Thorax: Scutum black, mainly dull pollinose, except white on notopleuron, and pollen concentrated on pair of anterior patches; scutum black pilose, except white on notopleuron and anterior to scutellum, usually with some black pile directly anterior to transverse suture; scutum with anterior row of scale-like white pile with shorter pile in the middle. Scutellum black, pile white, subscutellar fringe pile long and white. Pleuron white pilose and black. Plumula gray. Calypter gray, fringe darker. Halter stem light yellow to light brown, capitulum yellow.
Wing: Entirely hyaline to entirely brown, stigma usually darker, entirely microtrichose; alula hyaline, basally 1.7 times to apically 3.3 times as broad as c cell, entirely microtrichose.
Legs: All legs dark brown to black. Apex of profemur and base of protibia pale, apex of protibia and 2nd protarsomere usually pale. Apex of mesofemur, basal ¼ of mesotibia and first 2 mesotarsomeres usually pale. Basal ½ of metafemur sometimes pale, pale on apex of metafemur and base of metatibia, pale on apex of metabasitarsomere until 3rd or 4th metatarsomere, 4th metatarsomere sometimes brown, 5th metatarsomere dark brown; metacoxa and metatrochanter white pilose.
Abdomen: Black; 3.2 times as long as thorax. First tergite pile mainly white, sometimes with a few black pile basodorsally. Second tergite narrow and very long, length 7.5 times minimum width, sometimes pale on basolateral ⅓; 2nd tergite with a sub-basal and a sub-apical rounded maculae of dull black pollen which might join dorsally; 2nd tergite with long, erect and black pile, except appressed dorsally, and sometimes with white pile on baso-lateral ¾. Third tergite trapezoidal and long, length 3.4 times minimum width, sometimes with lateral subbasal pair of pale maculae; 3rd tergite with large central triangular region of dull black pollen, and with appressed and black pile, except white on baso-lateral ⅓. Fourth tergite sub-quadrate long, 1.2 times as long as wide, basolateral corners sometimes with small pale maculae; 4th tergite with central pair of triangular maculae of dull black pollen, and with appressed and black pile. Fifth tergite rectangular and wide, with small baso-median macula of dull black pollen, and with appressed and black pile. Genitalia: Cercus with 1 row of pile on medial margin and 4–5 irregular rows on lateral margin. Surstylus sub-quadrate with extended apical corner on lateral view, directed apically, with long setulae (around 14) ventrally on apical ¾ organized in transversal rows and 1–2 setulae basally, with very few pile (around 5) on basal ½ of the dorsal surface. Subepandrial sclerite rectangular and wide, with baso-lateral corners extended and directed basally (as long as sclerite), homogeneously sclerotized. Hypandrium with trapezoidal notch extending to anterior 3/5, notch posterior margin straight. Distiphallus with anterior surface almost straight. Postgonite with ventral surface slightly concave medially, dorsal surface straight, both surfaces curving gently towards acute dorsal extremity of apex.
Female: Similar to male except: Face sometimes pale on lateral ¼. Frons white pollinose maculae sometimes connected to pollen from face. Ocellar triangle 2–3 times its length from posterior eye margin and ~1 ocellus-width from lateral eye margin. Calypter sometimes entirely white. Wing hyaline but sometimes slightly dark on cells bc, c, sc, r, basal ⅓ of r1, base of r2+3 and bm. Metafemur sometimes with only a subapical dark ring. Second abdominal tergite 5 times minimum width, with shorter pile and lateral pile appressed on apical ½. Third tergite shorter, length 2.6 times minimum width. Fourth tergite rectangular and wide, 1.5 times wider than long. Fifth tergite rectangular and wide, 2.45 times wider than long. Sixth tergite rectangular and wide, much shorter than 5th tergite. Genitalia: 7th tergite rectangular, with concave posterior margin, baso-lateral corners very slightly extended, pilose on apical ½, sometimes narrower, with straight posterior margin and pile more sparse and bare on a narrow medial region; 7th sternite absent but ventral membranous region pilose. Eighth tergite sub-quadrate wide and posterior margin as on 7th tergite, anterior margin slightly concave, pilose on apical ½, anterior and posterior margins sometimes straight; 8th sternite unsclerotized medially, baso-dorsal corners slightly extended or not, entirely pilose. Tenth tergite modified and fused to cercus forming a pair of separate rectangular sclerites, with long narrow baso-lateral extensions usually directed ventrally, apical ½ slightly enlarged, sparse pilose on basal ¾, densely pilose and with setulae apically, apex sometimes curved in a ventral direction. Spermatheca with small protuberances on ½ of its surface, sometimes large.
Length. 5.5–9.5mm; wing 4–7mm.
Distribution. Brazil (Amapá, Amazonas, Bahia, Distrito Federal, Maranhão, Pará, São Paulo), Colombia (Amazonas), Ecuador (Cotopaxi, Los Ríos, Napo, Sucumbios), Guyana, Panama (Canal Zone), Peru (Cuzco, Madre de Dios), Suriname, Trinidad.
Material examined. UNKNOWN. Frank M. Hull Collection C.N.C. 1973 (1 ♀, CNC Diptera 161311). BRAZIL. Amapá, Serra do navio, Malaise trap suspended at 1.6m, 15–17 May 1989, A. L. Henriques (1 ♂, MPEG); Amazonas, Urucurituba, Exp. perm. Amaz., Oct 1969 (1 ♀, MZUSP); Bahia, Feira de Santana, 20 Apr 2001, Loyana (1 ♂, MZFS); Distrito Federal, Parque Nacional, 1100m., 3 Mar 1970, J. M. & B. A. Campbell (1 ♂, CNC Diptera 161309, 2 ♀, CNC Diptera 161312–3); Maranhão, Bacabal, 2 Jan 1989, Cazuza (1 ♀, MPEG); Pará, Belém, Pôrto do SESP, Exp. perm. Amaz., Sep 1969 (1 ♀, MZUSP); ..., Bragança, Malaise, 12 Mar 1983, R. B. Neto (1 ♀, MPEG); ..., Carajás, Dois Alfa Serraria, 14 Apr 1983, M. F. Torres (1 ♀, MPEG DIP 12170464); ..., Serra Norte, Manganes, 22 Apr 1986, M. F. Torres (1 ♀, MPEG DIP 12170440); São Paulo, Araçatuba, Córrego Azul, Mar 1947, M.P. Barretto (2 ♂, MZUSP); ..., Avanhandava, Feb 1946, M.P. Barretto (1 ♀, MZUSP); ..., Guaianazes, Feb 1950, M. Carrera (1 ♀, CNC Diptera 161314); ..., Rio Paraná, Porto Cabral, 20–31 Mar 1944, Trav. Fo. & Carrera & E. Dente (1 ♀, CNC Diptera 161315); ..., Com I. O. Cruz, Ilha Seca, 18–26 Feb 1940 (1 ♂, CNC Diptera 161308). COLOMBIA. [Amazonas], Leticia, 20–26 Feb 1972, A. Sauvé (1 ♀, CNC Diptera 161321). ECUADOR. Cotopaxi, Latacunga, 133 Km W, 1080’ at blacklight, 25 Jul 1975, Langley & Cohen (1 ♂, USNM ENT 00257719); Los Ríos, Rio Palenque, 0°35' S 79°22' W, 150m., 22–26 Feb 1976, G. & M. Wood (1 ♀, CNC Diptera 161316); Napo, Puerto Misahualli, 350m., Feb 1983, M. Sharkey (1 ♂, CNC Diptera 161310); [Sucumbios], Limoncocha, 0°24' S, 76°40' W, 250m., 9–16 Mar 1976, G. E. Shewell (1 ♂, CNC Diptera 161306). GUYANA. Mazaruni–Potaru District, Takutu Mountains, 6°15' N 59°5' W, 13 Dec 1983, P. J. Spangler & W. E. Steiner (1 ♂, USNM ENT 00257715). PANAMA. Canal Zone, Barro Colorado Island, Type Baccha zeteki Curran no [red label], 22 Dec 1928 & 28 Jan 1929, C. H. Curran (1 ♂, holotype Baccha zeteki, 1 ♀, allotype Baccha zeteki, AMNH); …, Summit, Nov 1946, N. L. H. Krauss (1 ♂, CNC Diptera 161304); …, 11 Dec 1928 (1 ♀, Paratype Baccha zeteki, AMNH); ..., 10 Jan 1929, C. H. Curran (1 ♀, CNC Diptera 161317) & 17 Jun 1978, Silberglied & Aiello (1 ♀, USNM ENT 00257716); ..., Frijoles, 10 Jul 1924, N. Banks (1 ♀, CNC Diptera 161318). PERU.
Cuzco, Quincemil, 780m., 13–31 Aug & 1–15 Nov 1962, L. Pena (1 ♂, AMNH, 2 ♀, CNC Diptera 161319–20); Madre de Dios, Avispas, 400m., 10–20 Sep 1962, L. Pena (1 ♂, CNC Diptera 161305, 1 ♀, AMNH); ..., Manu, Rio Manu, nr. Pakitza, 12°17' S 70°57' W, 250m., 9 Sep 1988, W. N. Mathis (1 ♂, USNM ENT 00257717). SURINAME. Murisburg [?], 19 Jun 1961, P. H. v. Doesburg Jr. (1 ♂, CNC Diptera 161307); Raleigh Va-len- Voltzberg Res Foengoe, 4°43' [N] 56°12' [W], 26 Jan–15 Feb 1982, J. Carpenter & D. Trail (1 ♂, USNM ENT 00257720). TRINIDAD. W. L., 2 mi. S Valencia, 5 Jan 1979, M. A. & L. L. Ivie (1 ♀, USNM ENT 00257718).
Comments. The holotype of Baccha crassa is missing its head, but information provided by Nigel Wyatt (Diptera curator at the BMNH), confirms that the remaining parts of the type specimen agree with this redescription.
Although the male and female types of B. zeteki at the AMNH had no label indicating which one is the holotype, Curran’s (1930) description states that the male is the holotype. Red labels indicating the holotype and the allotype were added to the specimens to make this distinction.
This species was still refered as O. zeteki in Miranda (2011).
description: Published as part of 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), pp. 1-154 in Zootaxa 3819 (1) on pages 90-92, DOI: 10.11646/zootaxa.3819.1.1, http://zenodo.org/record/251284