Metachela spinulosa, Camara, Josenir Teixeira & Rafael, Jose Albertino, 2017

Camara, Josenir Teixeira & Rafael, Jose Albertino, 2017, New species of Metachela Coquillett (Diptera, Empididae) from the Atlantic Forest, Brazil and a key to the Neotropical species, ZooKeys 714, pp. 129-140 : 133-136

Metachela spinulosa sp. n. Figs 12-18, 19-23

Type-locality.

BRAZIL, Minas Gerais, São Roque de Minas, Parque Nacional Serra da Canastra, Rio Rolador.

Type-specimen.

Holotype male, pinned, with abdomen in a microvial. Original label: "BRAZIL, MG[Minas Gerais], São Roque de Minas, Parque Nacional Serra da Canastra, Rio Rolador. Malaise, 15-18.xi.2014. J.L.Nissimian, A.L. Oliveira & A.P.M. Santos." (INPA). Paratypes. Same data as holotype (1 male, 3 females, INPA).

Diagnosis.

Scutum with a mid-longitudinal brown stripe; vein R2+3 fused to R1; male cercus with truncate apex and somewhat scattered spine-like setae; epandrium with an apicoventral acute projection; female tergite 8 with bilobate apex; female tergite 10 divided into two sclerotized plates separated by a membranous area.

Male (Fig. 12). Holotype: body length: 3.5 mm; wing length: 2.7 mm.

Head (Fig. 12): Dark brown to black, setae whitish. Ocellar triangle with two pairs of proclinate bristles, anterior pair stouter. Eyes iridescent black, separated on face. Occiput with scattered fine setae. Mouth parts yellow; proboscis short, right and with yellow setae. Antenna yellow, with scape and pedicel bearing distinct short ventral setulae; postpedicel approximately 2 × as long as wide; stylus very short, 0.1 × as long as postpedicel.

Thorax (Fig. 12): Elongate, slightly arched dorsally; scutum yellowish except for mid-longitudinal brown stripe, darker posteriorly, and brownish posterolateral spot above wing base; scutum with very small and fine yellow setae except for one notopleural, one postalar, and two pairs of small parallel scutellars; scutellum and mediotergite brown;

Legs (Fig. 12): Yellow. Fore coxa as long as distance between fore- and mid coxae, 3 × as long as wide, with some dorsoapical pale setae. Fore femur (Fig. 13) 1.2 × as long as fore coxa, 3.5 × as long as wide, with anteroventral row offour spines, anteroventral row of 4 denticles, and posteroventral row of 17 denticles, with basal one stouter; anteroventral row of denticles placed on distal half and posteroventral row restricted to distal 0.9, and both rows without apical discontinuity and diverging at apex. Fore tibia (Fig. 14) ~ 0.8 × as long as fore femur; with decumbent short pale setulae dorsally, denser apically. Mid femur with 2 anteroventral and 15 posteroventral spines, basal pair stouter. Hind legs slender with fine setae, except hind tibia with dorsoapical ‘comb’ of short setae.

Wings (Figs 12 and similar to 20 of female): Membraous, veins yellowish; vein R2+3 short, fused to R1; R4+5 fork angle around 70°; R5 and M1 slightly divergent at extreme apex; cell bm+dm ending beyond apex of R1, ~ 1.4 × as long as cell br. Halter whitish yellow.

Abdomen (Fig. 12): Tergites and sternites 1-6 and anterior margin of tergite 7 yellowish, membranous; posterior margin of tergite 7, tergite 8 and sternite 8 brownish; sternite 8 strongly sclerotized, U-shaped with lateral side upward directed posteriorly.

Male terminalia: Brown. Cercus wider on basal 1/3, apex truncate in lateral view (Fig. 15), with somewhat scattered spine-like setae (Fig. 16); left and right cerci closely approximated anterodorsally (Fig. 16). Epandrium with a posterodorsal pointed projection apically (Figs 17 and 18) and distinct strong setae on outer face (Fig. 17). Hypandrium membranous medially on basal half, with strong setae (Figs 15 and 18); gonocoxal apodeme projecting anteriorly as a small protuberance. Subepandrial sclerite subrectangular, more sclerotized basally and laterally (Fig. 17). Phallus strongly sclerotized, abruptly acute apically. Ejaculatory apodeme short, trilamellar.

Female (Fig. 19, 20). Similar to male. Tergite 7 brown, rectangular, shorter than tergite 8 (Figs 21 and 22); tergite 8 brown, elongate, bilobate posteriorly (Fig. 22); tergite 10 light brown, divided into two sclerotized plates separated by membranous area medially (Fig. 22). Cercus light brown, apex pale (Figs 21, 22 and 23). Sternite 7 light brown, concave on posterior margin (Fig. 23); sternite 8 brown, subrectangular (Fig. 23); sternite 10 light brown, v-shaped (Fig. 23). Body length: 3.9 mm; wing length: 3.1 mm.

Geographical records.

Brazil (Minas Gerais).

Etymology.

From the Latin spinosus (spine), referring to the spine-like setae on the male cercus.

Remarks.

Metachela spinulosa sp. n. differs from other species especially by the male cercus with scattered spine-like setae (absent in other species) and epandrium with an apicoventral acute projection (absent in other species).