Relictanum adspersitum

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 : 87-88

Relictanum adspersitum Miranda sp. nov.

Map 2. Figure 42 .

Type locality. Brazil, São Paulo, Campinas region, Fazenda Pau d’alho, 80 km NW São Paulo, 22°90'S 47°04'W. Holotype female CNC.

Male. Head: Black. Face narrow, almost straight dorsal to tubercle, lateral ¼ pale, white pilose, black ventral to antennal base. Lunule entirely black. Frontal triangle entirely black, black pilose with dull brown pollen divided medially by narrow bare vitta, white-silver pollen (continuous from face) restricted to lateral margin almost until eye contiguity. Frontal prominence slightly protuberant at level of frontal triangle. Vertical triangle with 1 median row of pile; ocellar triangle separated by its length from posterior eye margin. Eye contiguity slightly longer than vertical triangle length. Eye with posterior indentation at level of antennal insertion. Antennal insertions confluent. Antennae close together. Occiput entirely covered with white pollen, pollen sparse on dorsal ⅓, dorsal ⅓ with 1 row of simple black pile; middle ⅓ with 2–3 rows of white scale-like pile, posterior row longer, with some simple black pile on anterior row; ventral ⅓ with 2 rows of scale-like white pile.

Thorax: Scutum dark brown to black, dull brown-pollinose with a sub-median antero-postero pair of vittae and one median vitta of differently oriented pollen; scutum mainly white pilose, always with some black pile on notopleuron anterior to transverse suture, with anterior row of shining white pile interrupted in the middle. Scutellum dark brown to black, white pilose, subscutellar fringe pile long and white. Pleuron white pilose and black. Plumula white. Calypter gray with black margin. Halter light yellow.

Wing: Hyaline, bare on cell bc and basal ⅓ of c; alula large, 4 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 mesofemur and basal ½ of mesotibia pale. Apex of metafemur and basal ¼ of metatibia pale; mainly white pilose on metacoxa and metatrochanter.

Abdomen: Dark brown to black; about 2.7 times as long as thorax. First tergite with black pile baso-laterally, otherwise pile white; pile longer laterally. Second tergite long, length 2 times minimum width, with large medial fascia of dull black pollen and a pair of sub-lateral white spots; 2nd tergite with erect pile laterally and on basodorsal ¼, white on baso-lateral ¾, black and appressed on apico-dorsal ¾. Third tergite sub-quadrate, slightly longer than wide, with 4 white spots, a basal pair sub-laterally and a central pair; 3rd tergite with large triangular macula of dull black pollen medially, and with mainly appressed and black pile but with distinct shining white pile intermixed (best viewed from a dorso-anterior angle), pile slightly longer and erect on baso-lateral ½; 3rd sternite similar to tergite. Fourth tergite sub-quadrate and wide, always with 6 spots, and with erect and white pile restricted to baso-lateral corners; remaining characteristics as on 3rd. Fifth tergite rectangular and wide, with only a central pair of white spots, without erect lateral white pile; remaining characteristics as on 4th. Genitalia: Cercus with 1 row of pile on medial margin and 2–3 rows on lateral margin. Surstylus very long, crescent shaped, with large baso-dorsal crest and dorso-apical small projection, directed ventrally, without setulae, with weak pile throughout most of dorsal surface. Subepandrial sclerite rectangular and wide, slightly concave on anterior and posterior margins, uniformly sclerotized. Hypandrium flattened, rectangular and long, ventro-anterior ⅔ weakly sclerotized and hyaline. Phallapodeme ½ size of hypandrium, narrow and long. Distiphallus smooth, anterior surface almost straight. Postgonite narrow and long, with few pile baso-ventrally, ventral surface straight, dorsal surface slightly concave; postgonite apex convex anteriorly, without ventral extremity, but with posteriorly curved acute subapical dorsal extremity.

Female: Like male except: Face and frons entirely white pilose. Lunule pale above antennal insertions but not extended dorsally, with central triangular black maculae broadly connected to frons color. Frons narrow, white silver pollen concentrated on lateral margin, absent medially, sparse elsewhere. Vertex very narrow, ocellar triangle ~2 times its length from posterior eye margin and adjacent to lateral eye margin. Occiput entirely white pilose. Scutum with sub-median pair of white pollinose vittae. Pile white on scutum, scutellum and pleuron. Calypter white. Wing hyaline, bare on bc, basal ½ of c, basal ½ of r, basal ½ of bm and almost basal ½ of cu p. Basal ⅔ of protibia pale; pale areas of the legs more distinct than on male. First tergite entirely white pilose. Third tergite trapezoidal wide, 2 times wider than long. Fourth rectangular and wide. Sixth segment short, 3.4 times shorter than 5th segment. Genitalia: 7th tergite rectangular, with pile on apical ⅔; 7th sternite absent but with extensive membranous region (greater than the dorsal distance between the 6th and 8th segments). Eighth tergite notched anteriorly and posteriorly, leaving a narrow bridge between the 2 halves, 8th sternite divided into a pair of lateral lobes, joined basally. Tenth tergite notched anteriorly and with a convex posterior margin; 10th sternite reduced to a triangular sclerite. Cercus basally fused by narrow strip to lateral margin of 10th tergite, densely pilose and with setulae directed basally on dorsum.

Length. 6.5–7.5mm; wing 5–6mm.

Distribution. Brazil (Santa Catarina, São Paulo).

Primary type. Holotype: Female in good condition. Holotype labels: ‘Fazenda Pau d’alho // 80 km N.W. Sao Paulo // 28–29.X.1972 BRAZIL // R.V. Peterson’ ‘CNC DIPTERA // # 161188 ’ ‘ Holotype // Relictanum // adspersitum // G.F.G. Miranda’ [red label].

Paratypes. BRAZIL. Santa Catarina, Nova Teutônia, 300–500m, 27°11'S 52°23'W, 27 Dec 1959 & 22 Nov 1960, F. Plaumann (1 ♂, CNC Diptera 161190, 1 ♀, CNC Diptera 161189).

Comments. The markings of the abdomen resemble P. adspersa ( Fabricius, 1805) , but the silver pollen restricted to the sides of the frontal triangle/frons, the divided female 6th segment and the unmodified female genitalia of R. adspersitum set these two species apart. The surstylus and hypandrium of this species are distinct from other Relictanum species.

A female was chosen as a holotype since the specimen was in better condition than the available male.

Etymology. The specific epithet is a reference to Pelecinobaccha adspersa , a similar species. It is to be treated as a noun in apposition.

Figures

FIGURE 42. Relictanum adspersitum sp. nov. a – b. Holotype, female: a. Habitus, dorsal. b. Abdomen, dorsal. c – d. Female genitalia: c. Dorsal. d. Lateral. e – h. Male genitalia: e. Epandrium, lateral. f. Epandrium, ventral. g. Hypandrium, lateral. h. Hypandrium, ventral. 8 tg: 8 th tergite, 10 tg: 10 th tergite, cerc: cercus, s scl: subepandrial sclerite.