Macrostomus megatarsus Rafael & Vasconcelos 2024, sp. nov.
Creators: name: Rafael, José Albertino
name: Vasconcelos, Manuela Santos
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Empididae
Macrostomus
Macrostomus megatarsus

description: Macrostomus megatarsus sp. nov.
(Figs 1A–J, 2A–G, 5)
urn:lsid:zoobank.org:act: 9EA18821-7573-40F9-A55C-158B519E2E83
Diagnosis. Yellow to brown, except postcranium black and abdomen darker with blue reflection; male fore tarsomere 1 slightly thickened; wing brown, distinctly hyaline spotted; cell r1 without hyaline spot; Abdomen dark with steel (blue) reflection; tergite 8 with short bifid distal projection; posterior cercus lobe acute, elbowed, inward directed. Female: mid femur, hind femur, and hind tibia with dorsal and ventral pennate scales; sternite 8 widened (Fig. 2D, E), laterally with oblique median sinus with a small sclerite; genital fork (Fig. 2D) thin, Y-shaped, with lateral arms longer than basal arm.
Description. Holotype male. Body length 4.7 mm; wing length 4.5 mm. Habitus (Fig. 1A). Head narrowly dichoptic. Frons shiny brown to black, narrower than anterior ocellus width. Face slightly wider than frons, gray pruinose. One pair of proclinate ocellar setae. Postcranium shiny black, sparsely gray pruinose. Antenna with scape and pedicel yellow to light brown, postpedicel velvety dark brown to black, 6X longer than scapus + pedicel. Proboscis as long as head height (Fig. 1A). Thorax (Fig. 1A) shiny yellow-brown, more distinctly graybrown pruinose on posterior disc of scutum, on scutellum, and mediotergite. Postpronotal lobe, ventral margin of notopleuron and mesopleuron light brown to yellow. Setae: 3–4 antepronotals; 1 postpronotal stouter, 2 tiny; 2–3 proepisternals, with one longer; 4 dorsocentrals, two median pairs weaker; 3 notopleurals; 1 supra-alar presutural; 1 supra-alar postsutural; 1 postalar; 2 scutellars, outer weaker; 3 katatergitals stouter on anterior row and 2 weaker on posterior row. Legs (Fig. 1A) shiny yellow with all femora narrowly shiny black distally, apical fourth of hind tibia, and all tarsomeres 4–5 brown. Hind femur thickened on distal half; fore tarsomere 1 slightly thickened. Hind tibia with 10–12 slender anterodorsal and posterodorsal longer setae; hind tarsomere 1 with 1–2 dorsal longer setae. Wing (Fig. 1B) brown infuscate with hyaline spots. Halter light brown, knob slightly darker. Abdomen (Fig. 1A) shiny yellow-brown with blue reflection in certain light; tergites 1–2 and sternites 1–3 yellow. Tergite 8 (Fig. 1C, D) with short bifid distal projection. Terminalia shiny brown. Epandrium (Figs 1E, F) with anterodorsal lobe higher and stouter than posterodorsal lobe. Cerci with anterior cercus lobe short and narrow with median cercal bridge widened medially and protracted ventrally when seen in lateral view (Fig. 1E, G, H); median cercus lobe small, membranous with long setae (Fig. 1E, G); posterior cercus lobe acute, elbowed, inward-directed, with many long slender setae at margin, anteroventrally with thin process with few yellow apical setae. Subepandrial sclerite (Fig. 1H) widely opened, somewhat laterally extended. Hypandrium wider distally, with many slender posteromedial setae and large somewhat translucent spot medially (Fig. 1I). Ejaculatory apodeme tetralamellar (Fig. 1I). Phallus slightly longer than hypandrium.
Female. Habitus (Fig. 2A). Body length mean 3.7 mm (n = 5). As in males, except frons slightly narrower than anterior ocellus width, wider than face; fore tarsomere 1 not thickened; mid femur, hind femur, and hind tibia with dorsal and ventral pennate scales; wing (Fig. 2B) slightly wider than in male. Abdomen entirely shiny black, including terminalia less shiny than in male and sparsely gray pruinose. Terminalia (Fig. 2C–F). Tergite 8 (Fig. 2C) slightly concave basally and deeply concave apically. Sternite 8 (Fig. 2D, E) with oblique median sinus laterally with small sclerite. Genital fork (Fig. 2D) Y-shaped, thin with lateral arms longer than basal arm, somewhat curved. Spermatheca (Fig. 2F) spherical. Eggs oval (Fig. 2G). Variations. Male body varying from 3.4–4.8 mm; 3–5 dorsocentral setae; 3–5 antepronotals; 2–5 proepisternals; 1–5 anatergitals. Amapá specimens with postalar callus yellow, halter with knob whitish and terminalia yellow.
Geographic records. Brazil (Pará, Serra Norte); (Amapá, Oyapock); French Guiana (Patawa and Régina).
Type examined. HOLOTYPE ♂, labelled: “BRASIL, Pará, Serra Norte, Pojuca [~ 6°4′S 50°3′W], 14.v.1984 ” “ Brasil, Pará, T. Pimentel” “Holotype ♂, Macrostomus megatarsus ” “ MPEG ” (Fig. 1J). PARATYPES: Brasil: Pará, Carajás, Est. Manganês, 29.iv.1983 [~ 6°4′S 50°3′W], arm. Malaise, Mascarenhas e equipe (4♂, 1♀ MPEG, 1♂ CNC); idem, 06.v.1984 (1♀ INPA); idem, Est. Manganês 22.v.1984 (1♂ INPA); same data as holotype (3♂ 2♀ INPA, 3♂ MPEG, 3♂ MZUSP); idem, Fofoca [~ 6°4′S 50°3′W], 18.v.1984 (1♂, 1♀ MNRJ); idem, F. R. Ramos (1♀ MPEG); idem, 21.v.1984, Caldeirão (2♂ MPEG, 1♂, 1♀ INPA), 2♂ MZUSP, 2♂ MNRJ); Serra Norte, 10– 13.ii.1986, M.F. Torres & R. Neto, arm. Suspensa, 1, 6 m [1.6 meters above soil] (2♂ MPEG, 2♂ CNC). Amapá, Oiapoque, BR 156, km 25, 3°39′35″N 51°46′17″W, 10–25.vii.2019, Malaise, floresta, J.A. Rafael, S.P. Lima, F.F. Xavier F° (1♂ INPA); idem, 25.vii.–9.viii.2019 (1♂, 1♀ INPA); idem, 9–23.viii.2019 (1♂ INPA); idem, 23.viii.– 6.ix.2019 (1♀ MPEG); idem, 1–16.i.2020 (1♂ MZUSP); idem, 14–28.ii.2020 (1♂ MNRJ); idem, iii–vii.2020 (2♂ INPA). French Guiana: Patawa, 4°32.658′N 52°09.132′W, 180 m, viii.2008, MT, rainforest, J. Cerda (1♂ CNC); Régina: Kaw, Kaw Mountains, Point Road 40, ca. 300 m, 12.ii.–3.iii.2007, MT [Malaise trap], Keijo Sarv (1♂ CNC); idem, 3–27.iii.2007 (1♂, 1♀ CNC) (French Guianan specimens det. B.J. Sinclair, CNC).
Holotype condition. Good, abdomen not dissected, left wing mounted on microslide, pinned along with the specimen.
Etymology. From Greek megas = large, great, in reference to the enlarged fore tarsomere 1.
description: Published as part of Rafael, José Albertino & Vasconcelos, Manuela Santos, 2024, 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, pp. 429-438 in Zootaxa 5433 (3) on pages 431-433, DOI: 10.11646/zootaxa.5433.3.9, http://zenodo.org/record/10954401