Mimapsilopa onssa Mathis, Costa & Marinoni n.sp.

Figs. 16–22, 48, 52.

Diagnosis. This species is distinguished from congeners by the following combination of characters: Generally very dark brown, shiny. Moderately small to medium-sized shore flies, body length 2.00– 3.50 mm. Head (Figs. 16–18): Frons black, very sparsely microtomentose, subshiny to shiny; 2 proclinate fronto-orbital setae, anterior seta 3– 4 X length of posterior seta, posterior seta immediately laterad of large, reclinate fronto-orbital seta. Basal flagellomere brownish black, some specimens with faint orange coloration basoventrally, length nearly twice height, apex rounded; arista with 9–11 dorsal rays. Face black, polished, shiny, with very shallow, faint, vertical striae. Maxillary palpus black. Eye ratio: 0.61–84; gena-to-eye ratio: 0.11–0.14. Thorax: Mesonotum microsculptured; anepisternum dark brown, shiny. Wing (Fig. 48) with anterior margin infuscate, becoming less so to hyaline posteriorly, darkened portion in cell r1 with basal 1/4 noticeably paler than dark brown apical 3/4; wing length 1.80–2.50 mm; costal ratio 0.63–0.67; M vein ratio 0.61–0.67. Knob of halter white, stem yellowish. Femora and tibiae black (brownish black in specimens taken from alcohol); foretarsus brownish yellow ventrally; mid- and hindtarsi with basal 2–3 tarsomeres yellow to brownish yellow, apical 2 tarsomeres blackish brown. Abdomen: Tergites sparsely microtomentose; tergites 4, 5 about equal in length, both longer than tergite 3; tergite 5 bare, shiny. Male terminalia (Figs. 19–22): Epandrium in posterior view (Fig. 19) moderately setulose, shape as an inverted, thin to thick-walled U, narrowed dorsally between dorsal margin of cercal cavity and anterodorsal margin, lateral arms about equally wide, ventral margin shallowly emarginate; in lateral view (Fig. 20) with height about twice width, widest subventrally, dorsal 2/3 tapered, anterior margin with convexity on ventral half, posterior margin more or less evenly rounded; cercus in posterior view (Fig. 19) irregularly lunate, tapered toward apical angle, apical curved medially, in lateral view (Fig. 20) irregularly semicircular, curvature more abrupt dorsally; presurstylus symmetrical, in posterior view (Fig. 19) as a bilobed structure, with median lobe much shorter, rodlike, bearing a long, stout seta apically that is oriented posteromedially, a much longer and wider lateral lobe, length equal to height of epandrium, lateral margin shallowly and irregularly sinuous, medial margin emarginate on basal third, thereafter ventrally straight, in lateral view with irregularly quadrate base, apical half shallowly curved, almost parallel sided, slightly tapered, apex rounded; postsurstylus in lateral view (Fig. 22) clavate, greatly expanded towards apex, apex with a small, thumb-like process and emargination, in ventral view (Fig. 21) as lateral, wing-like extensions; pregonite in lateral view (Fig. 22) short, rod-like, in ventral view (Fig. 21) robustly ovate, short; postgonite short, closely associated with lateral arms of subepandrial plate, not well developed; subepandrial plate in lateral view (Fig. 21) bar-like, elongate, both apices tapered, in ventral view (Fig. 22) Vshaped, acutely pointed apically; aedeagus in lateral view (Fig. 22) with wide base, thereafter abruptly narrowed, apical 2/3 somewhat clavate, rounded apex, in ventral view (Fig. 21) urn-like, with sub-basal emarginations, apical ovate, apex bluntly rounded; phallapodeme lateral view (Fig. 22) roughly and irregularly triangular, short and wide, apex (attached to base of aedeagus) more broadly rounded than angle that attaches with hypandrium, in ventral view T-shaped with crossbar as long as stem; hypandrium a deep pocket in lateral view (Fig. 22) with a deep Ushaped invagination medially, in ventral view (Fig. 21) with anterior margin widely arched, posterior margin narrowed, somewhat truncate posteriorly.

Type material. The holotype male is labeled MATHINHOS. Paraná. Brasil [.] Parque Rio da Onça (25°50'S, 48°30'O), 27/IV2007 [,] E. R. Sepka col/ Holotype ♂ Mimapsilopa onssa Mathis, Costa,&Marinoni DZUP [red]. The holotype is double mounted (glued to a paper triangle), is in excellent condition, and is deposited in DZUP. Five paratypes (3♂, 2♀; DZUP, USNM) bear the same label data as the holotype. Other paratypes (1♂, 2♀; DZUP, USNM) bear the same locality data as the holotype but with the date of 27 Jan 2010.

Type locality. BRAZIL. Paraná: Matinhos (Rio da Onça; 25°47.1'S, 48°31.6'W; 3 m).

Etymology. The species epithet, onssa, refers to the type locality, Rio da Onça in the municipality of Matinhos, Brazil. The name is a noun in apposition. The Portuguese cognate onça also refers to the Jaguar ( Panthera onca L.).

Distribution (Fig. 52). Neotropical: Brazil (Paraná).

Remarks. Although M. onssa is similar to M. acta and M. iguassu, the latter two species also of the cressoni group, it is distinguished from the latter two species by the largely bare, and somewhat polished and shiny face in addition to the shape of the presurstylus, which is unmistakable, especially the elongated, narrow, and somewhat pointed and paired prolongations. These are usually visible in pinned specimens, facilitating recognition. In other congeners, the presurstylus is usually bluntly to narrowly rounded.