Macrostomus nitidus, Rafael, José Albertino & Cumming, Jeffrey M., 2012

Rafael, José Albertino & Cumming, Jeffrey M., 2012, Revision of the genus Macrostomus Wiedemann (Diptera, Empididae, Empidinae). III. The limbipennis species-group, Zootaxa 3361, pp. 45-55 : 51-53

Macrostomus nitidus , sp. nov.

( Figs. 32–43 )

Diagnosis. Postgenal and antepronotal setae weaker than dorsal thoracic setae. Thorax and legs predominantly yellow. Abdomen shinning black. Male wing infuscated at apex; female wing infuscated at costal margin. Flagellum short pilose. Posterior tibia with long setae. Hypandrium distinctly wider at apex.

Description. Holotype male. Body length 3.0 mm; wing length 3.9 mm. Head with frons shining black, as large as anterior ocellus width. Face less shining black, as wide as frons, slightly gray pruinose at apex. Ocellar tubercle slightly protuberant with 2 pairs of ocellar setae, posterior pair minute. Postcranium black, gray pruinose. Antenna velvety black with pedicel yellowish. Flagellum pubescent, with 3 flagellomeres. Proboscis yellow, brown at base. Palpus light brown to yellow. Thorax shining yellow with scutum and scutellum darker with more distinct gray pruinescence. Postpronotal and postalar lobes yellow. Depending on light incidence, in anterior view scutum with wide, dark stripe or 2 narrow dark stripes between dorsocentral setae. Thoracic setae: 4 dorsocentrals with posterior stronger; 3 postpronotals with 1 longer; 3 notopleurals with posterior stronger; 2 pairs of scutellars with inner pair slightly convergent; 4 antepronotals; 2–3 proepisternals; 6 katatergitals with anterior row stronger; other setae as described for limbipennis species-group (diagnosed above). Legs shining yellow with apices of hind femur, fore tibia and mid tibia darker. Hind tibia and all tarsi black with fore tarsomeres 1–4 white distally. Femora/tibiae setae slightly stronger: fore tibia ( Fig. 32 ) with 1 anterodorsal seta near base, 1 posterior near middle; mid femur ( Fig. 33 ) with 1 strong anterior seta near apex; mid tibia with 2 anterodorsals, 1–2 posterior along basal half, 1–2 anteroventral at middle of distal half; hind femur ( Fig. 34 ) with 2 anterior setae, 1 at basal fifth and 1 at distal fifth, 1 stronger anteroventral at base of distal third, and other slender anteroventral setae; hind tibia with 5–6 slender dorsal setae. Hind tarsomere 1 with 1 longer dorsal and short spine-like setae ventrally. Wing ( Fig. 35 ) hyaline, brown infuscated at distal margin. Cell dm truncate. Veins M1, M2 and A1 evanescent. Halter light yellow to white. Abdomen shining black with blue reflection in certain lights; lateral bristles longer. Sternites concolorous with tergites. Tergite 8 ( Fig. 36 ) with small projection inside median distal sinus. Epandrium ( Fig. 37 ) with anterodorsal and posterodorsal lobes of same height with deep sinus. Anterior cercus very large with internal sinus; posterior cercus elongate; median lobe membranous with long setae. Hypandrium ( Fig. 38 ) with many setae along posterior margin, with wider apex. Ejaculatory apodeme with short dorsal lamella.

Female. Body length 3.4 mm; wing length 3.7 mm. Frons and face wider than anterior ocellus width and wider than in male. Wing ( Fig. 39 ) with cell r1 and base of cell r2+3 brown infuscated. Fore tarsi unicolorous. Tergite 8 ( Fig. 40 ) with median and basal heavily sclerotized area. Sternite 8 ( Figs. 41, 42 ) distinctly curved with anterior third thinner, ventrally more sclerotized at median third. Tergite 10 with basal incision ( Fig. 40 ) [cerci broken]. Genital fork ( Fig. 43 ) small. Genital chamber membranous.

Geographical distribution. Brazil (Goiás, Mato Grosso).

Type Material. HOLOTYPE ɗ: “[ BRASIL], Est[ado] de Goiás, Corumbá, F.[azenda] Monjolinho, 11–945 [xi.1945], Barreto col.” // “ Macrostomus nitidus Holótipo ɗ” ( MZSP). PARATYPES. Same data as holotype (1ɗ, 1Ψ, MZSP; 1ɗ, INPA). Mato Grosso, Chapada dos Guimarães [15 ° 26'13.7''S 55 ° 47'27.0''W], 22–30.xi.1983, J.E. Bindá, arm. Malaise ( INPA) (4ɗ, INPA; 3ɗ, CNC).

Etymology. From Latin nitidus = shining, in reference to the shining black abdomen.

Figures

FIGURES 32 – 38. Macrostomus nitidus, sp. nov. 32 – 35, paratype male from Goiás, Brazil; 32, left fore leg, posterior view; 33, left mid leg, anterior view; 34, right hind leg, anterior view; 35, wing; 36 – 38, holotype male; 36, tergite 8, dorsal view, right setae omitted; 37, terminalia, lateral view; 38, hypandrium and phallus, lateral view. Scales: 32 – 34 = 0.5 mm; 36 – 38 = 0.2 mm.

FIGURES 39 – 43. Macrostomus nitidus, sp. nov. paratype female from Goiás, Brazil; 39, wing; 40, tergite 8, 10 and cercus (cercus broken), dorsal view; 41, sternite 8, lateral view; 42, sternite 8, 10 and cercus (cercus broken), ventral view; 43, genital fork, ventral view. Scales: 40 – 42 = 0.2 mm; 43 = 0.1 mm.