Planinasus atriclypeus, Mathis, Wayne N., Rung, Alessandra & Kotrba, Marion, 2012

Mathis, Wayne N., Rung, Alessandra & Kotrba, Marion, 2012, A revision of the genus Planinasus Cresson (Diptera, Periscelididae), ZooKeys 225, pp. 1-83 : 51-53

13. Planinasus atriclypeus sp. n. Figures 3470-72

Description of male.

Moderately small to medium-sized flies, body length 2.60-3.15 mm.

Head: Head ratio 0.62-0.65; frons generally uniformly brownish black to black, mostly very finely and sparsely microtomentose, subshiny to shiny, except for more densely microtomentose, anterolateral angles and slightly undercut anterior margin; anterolateral angles setulose; frons wider than long, frontal ratio 0.53-0.57; interfrontal seta shallowly curved, moderately elongate, about 2/3 length of lateral vertical seta. Antenna mostly uniformly black; some specimens with ventral portion of basal flagellomere and pedicel faintly yellowish brown; basal flagellomere moderately short, length at most only slightly greater than height at base, tapered gradually to narrowly rounded acute, dorsal and ventral margins nearly straight;; pedicel with ventral projection short, length of projection conspicuously less than length of pedicel without considering projection, bearing long, ventroapical seta (extended slightly beyond apex of basal flagellomere), 1 dorsoapical seta, 1 dorsal seta; arista bearing 13-14 dorsal rays, 3-4 ventral rays. Face comparatively narrow, facial ratio 0.34-0.37; portion dorsad of transverse carina moderately large, sparsely microtomentose, subshiny to shiny, mostly brownish to bluish black; antennal grooves especially shiny; ventrad of transverse carina more densely microtomentose, yellowish brown medially, moderately sparsely silvery yellow microtomentose, sericeous, lateral portions of face becoming bluish black; large facial setae arranged in approximately 2 transverse rows; dorsal row with 6 setae, medial pair of dorsal row moderately widely separate, shallowly dorsoclinate; next setae much shorter, shallowly ventroclinate; ventral row with 6 setae, all ventroclinate, medial pair slightly shorter than others. Clypeus brownish black to black with very sparse whitish yellow microtomentum; palpus brownish black.

Thorax: Mesonotum generally brownish black to deep bluish black, thinly microtomentose, subshiny to shiny; postpronotum brown, some specimens with some yellowish coloration around margin; area from postpronotum and through notople uron at most finely and thinly microtomentose, subshiny to shiny; pleural areas finely microtomentose, subshiny, blackish brown; anepisternum mostly bare but with 1-2 setulae along posterior margin; katepisternum generally setulose, bearing 2 setae toward dorsal margin. Wing without pattern, generally infumate. Coxae and trochanters yellow; Femora and tibiae mostly brownish black; forefemur lacking a preapical annulus; tarsi mostly yellowish basally, apical 3-4 tarsomeres becoming darker; forefemur bearing 1 seta at apical 1/3 along posteroventral surface.

Abdomen: Uniformly blackish brown, mostly dull to faintly subshiny, moderately invested with microtomentum. Male abdomen: Tergites 1+2-6 well developed, lengths of tergites 3-6 subequal; tergite 7 narrow; sternites 3, 4, 5 generally as rectangular plates, slightly wider than long, lateral margins shallowly arched; sternite 5 with lateral margins nearly straight, posterior margin of sclerotized portion nearly straight; sternite 6 apparently absent; sternite 7 very narrow, band-like, lightly sclerotized medially, forming an annulus with tergite 7. Male terminalia (Figs 70-72): Epandrium in lateral view (Fig. 70) trapezoidal, higher than wide, narrowed dorsally, anterior and posterior margins nearly straight; surstylus as long as epandrium, extended from ventral margin of epandrium in nearly straight to slightly oblique alignment with it, in lateral view (Fig. 70) elongate, robustly developed, unevenly bilobed apically, anterior lobe much larger, digitiform, rounded apically, short posterior lobe shallowly pointed, bearing medial, elongate setula; hypandrium in ventral view (Fig. 71) broadly and robustly U-shaped, arms tapered, narrowed toward attachment with epandrium, anterior portion robustly developed, anterior margin shallowly pointed; pregonite roughly triangular (Fig. 71), with anterior margin significantly receded and slightly round corners; postgonite in ventral view (Fig. 71) convoluted, bearing digitiform lobe with 6 apical and marginal setulae, in lateral view (Fig. 72) lobe 4 apical, short setulae are seen; phallus in ventral view difficult to discern, in lateral view (Fig. 72) longer than wide, slender, with pointed apex and posterior fine hairs; phallapodeme in lateral and ventral views (Figs 71-72) elongate, shallowly sinuous to nearly straight; ejaculatory apodeme greatly reduced.

Description of female.

As in male except as follows: Head generally slightly narrower, head ratio 0.65-68; frontal ratio 0.44-48; facial ratio 0.34-37. Face mostly uniformly bluish black, silvery white microtomentum more evident.

Type material.

The holotypes male is labeled "Floresta da Tijuca- BRASIL/30 XII 1991 A. BAPTISTA R. BAPTISTA em Marantaceae [date and name of plant family handwritten]/USNM ENT 00118276 [plastic bar code label]/HOLOTYPE ♂ Planinasus atriclypeus Mathis & Rung MZUSP [red]. The holotype is double mounted (glued to a paper point), is in good condition, and is deposited in the MZUSP. Eleven paratypes (5♂, 6♀; MZUSP, USNM) bear the same locality label as the holotype. Other paratypes are as follows: Brazil. Rio de Janeiro: Parque Nacional de Itatiaia, Maromba (22°29.7'S, 44°33.7'W), 13-17 Dec 1991, A. and R. Baptista (2♂, 1♀; MZUSP, USNM).

Type locality.

Brazil. Rio de Janeiro: Rio de Janeiro, Floresta da Tijuca (22°57.6'S, 43°16.4'W).

Other specimens examined.

BRAZIL. Rio de Janeiro: Nova Friburgo (22°17.2'S, 42°32'W), 1 May 1995, A. and R. Baptista (1ex (abdomen missing); USNM); Paineiras, Teresópolis (22°24.3'S, 42°58.3'W), 5 Feb 1995, A. and R. Baptista (1♂; USNM); Parque Estadual do Desengano (near Santa Maria Magdalena; 21°53'S, 41°55'W), 19-23 Dec 1991, A. and R. Baptista (1♂; MZUSP). São Paulo: Salesópolis (23°31.9'S, 45°50.8'W), 1-3 Mar 1992, A. and R. Baptista (1♂; USNM).

Distribution

(Fig. 34). Neotropical: Brazil (Rio de Janeiro, São Paulo).

Etymology.

The specific epithet, atriclypeus, is of Latin derivation and refers to the black clypeus, a diagnostic feature of this species.

Remarks.

This species is most similar to Planinasus atrifrons . Besides the characters given in the key, it can be distinguished from that species by structures of the male terminalia, particularly the unevenly bilobed surstylus, with anterior lobe much larger, digitiform, rounded apically, and a short, shallowly pointed posterior lobe. In Planinasus atrifrons , the surstylus is swollen medially, and the apex makes a nearly right angle with the main surstylar apex (Fig. 73).