A new species-group of Macrostomus (Diptera, Empididae) with notable spotted wings recorded from the North Amazonia biogeographical component and a key to species-groups Author Rafael, José Albertino Instituto Nacional de Pesquisas da Amazônia (INPA), Coordenação de Biodiversidade, Manaus, Amazonas, Brazil Author Vasconcelos, Manuela Santos Instituto Nacional de Pesquisas da Amazônia, INPA, Scientific Initiation Program, Manaus, Amazonas, Brazil text Zootaxa 2024 2024-04-08 5433 3 429 438 http://dx.doi.org/10.11646/zootaxa.5433.3.9 journal article 10.11646/zootaxa.5433.3.9 1175-5326 10954401 3ED6D283-A033-485F-9632-FC95778F3A44 Macrostomus polleti sp. nov. ( Figs 3A–I , 4A–F , 5 ) urn:lsid:zoobank.org:act: 784CFBA7-3F32-4DB4-A44B-82ACDC440F70 Diagnosis. Yellow to brown, except postcranium black; male fore tarsomere 1 not thickened, whitish; wing brown, distinctly hyaline spotted; cell r 1 with small hyaline spot at level of cell dm spot. Abdomen darker with blue reflection; tergite 8 rounded distally, without distal projection. Posterior cercus thin, upward directed. Hypandrium thin distally, posterior margin with a distinct median acute process. Female: Mid femur, hind femur, and hind tibia with dorsal and ventral pennate scales; sternite 8 ( Fig. 4D, E ) with distal half uniformly narrowed, with no median sinus laterally. Genital fork thin, elongated, Y-shaped, with lateral arms slightly shorter than basal arm. Description. Holotype male . Body length 4.8 mm ; wing length 4.5 mm . Male ( Fig. 3A ) identical to previous species, except by frons dichoptic as wide as anterior ocellus width, wider than face; halter with knob whitish; fore tarsomere 1 not thickened, somewhat whitish. Hind tibia with 6 longer dorsal setae. Wing ( Fig. 3B ) distinctly spotted; cell r 1 with small hyaline spot at level of cell dm spot ( Figs 3B , 4B ). Abdomen shiny black with blue reflection. Tergite 8 ( Fig. 3C–D ) rounded distally. Terminalia ( Fig. 3E–H ) concolorous with abdomen. Epandrium with anterodorsal and posterodorsal lobe same height; anterior cercus upward directed, with narrow median cercal bridge ( Fig. 3E, F ); posterior cercus slender, elongated, upward directed ( Fig. 3E, G ). Hypandrium ( Fig. 3H ) with small somewhat translucent spot basally, distal half of hypandrium thin, posterior margin with distinct median acute process ( Fig. 3H ). Ejaculatory apodeme tetralamellar ( Fig. 3H ). Phallus slender ( Fig. 3H ). FIGURE 3. Macrostomus polleti sp. nov. , paratype male. A, habitus; B, wing; C, tergite 8 and sternite 8, dorsal view; D, tergite and sternite 8, lateral view; E, terminalia, lateral view (epandrium outlined); F, detail of the cercal bridge and subepandrial sclerite, anterior view; G, cerci lobes, posterior view; H, hypandrium (below) and detached phallus and ejaculatory apodeme, lateral view. I, holotype labels. Abbreviations: a ce = anterior cercus; ce brd = cercal bridge, m ce = median cercus, p ce = posterior cercus, ph = phallus, sbepand scl = subepandrial sclerite. Female. Habitus ( Fig. 4A ). Body 4.7 mm ; wing 4.6 mm . As in males, except mid femur, hind femur, and hind tibia with dorsal and ventral pennate scales; wing slightly wider than in male ( Fig. 4B ). Abdomen entirely shiny black, including terminalia less shining than in male and sparsely gray pruinose. Terminalia ( Fig. 4C–F ). Tergite 8 ( Fig. 4C ) slightly concave basally, deeply concave apically. Sternite 8 ( Fig. 4D, E ) with distal half uniformly narrowed, with no median sinus laterally. Genital fork ( Fig. 4D ) Y-shaped, with lateral arms as long as basal arm and somewhat straight. Spermatheca ( Fig. 4F ) spherical. FIGURE 4. Macrostomus polleti sp. nov. , paratype female. A, habitus; B, wing; C, tergites 8, 9+10 and cerci, dorsal view; D, sternite 8 and genital fork, ventral view; E, tergite and sternite 8 to cerci, lateral view; F, spermatheca and spermathecal duct. Figures C, D, and E at same scale. Variations. Male body varying from 4.5–4.8 mm ; 3–4 dorsocentral setae; 3–4 antepronotals; 2–5 proepisternals; Amapá specimens with thorax yellow-brown; Mitaraka specimens with thorax brown, halter with knob whitish and terminalia slightly black. Geographical records. Brazil ( Amapá , Serra do Navio, Oyapock); French Guiana (Mitaraka). Material examined. HOLOTYPE ♂ , labelled: “BRASIL, Terr. [ Território ] Amapá , Serra do Navio [ 0°53′N 52°0′W ], 14.x.1957 , J. Lane leg,”, “ Holotype ♂ , Macrostomus polleti ”, “ MZUSP ” ( Fig. 3I ) . PARATYPES : Brazil : Same data as holotype, except: 26.ix.1957 ( 1♂ MZUSP ); Amapá , Oiapoque , BR 156 , km 25, 3°39′35″N 51°46′17″W , iii–vii.2020 , Malaise , floresta, J.A. Rafael , S.P. Lima & F.F. Xavier F° ( 1♂ INPA ) . French Guiana : Mitaraka , 02°13′59.8″N 54°27′46.5″W , 471 m , partially opened areas on savanna, roche 2, 13–20.viii.2015 , MT [ Malaise trap ] ( 6m ), leg. Pierre-Henri Dalens –sample code: Mitaraka /230 ( 1♂ , 1♀ MNHN ) . Holotype condition. Mounted, in good condition, not dissected. Etymology. The specific name is in honor of Dr. Marc Pollet, coordinator of the French Guiana project in Mitaraka.