Mimapsilopa plaumanni Mathis, Costa & Marinoni n.sp.

Figs. 23–30, 51, 52.

Diagnosis. This species is distinguished from congeners by the following combination of characters: Generally very dark brown to black, shiny, small shore flies, body length 2.30–2.80 mm. Head (Figs. 23–25): Frons dark brown, sparsely microtomentose. Basal flagellomere mostly yellow, some specimens with darkened dorsal margin, only very slightly tapered, apex moderately broadly rounded; arista with 8–9 dorsal rays. Face dark brown to black, shiny, shallowly swollen, ventral half microsculptured with fine transverse striae. Eye ratio: 0.62–65; gena-to-eye ratio: 0.17–0.20. Thorax: Scutum, including notopleuron, dark brown microtomentose, more densely so than frons but still subshiny; scutellum and notopleuron microtomentose; anepisternum, anepimeron, and katepisternum dark brown to black, shiny. Wing (Fig. 51) faintly brown to golden, mostly hyaline, lacking maculation pattern; length 2.60 mm; costal ratio 0.80–84; M vein ratio 0.60–65. Knob of halter white, stem yellowish. Foreleg including forebasitarsomere and femora and tibiae of mid- and hindlegs dark brown; extreme apex of mid- and hindtibiae and mid- and hindtarsi yellow except for darkened apical tarsomere. Abdomen: Tergites sparsely microtomentose; Tergites 4, 5 about equal in length, both longer than tergite 3; tergite 5 bare, shiny. Male terminalia (Figs. 26–30): Epandrium in posterior view (Fig. 26) setulose with short, stout setulae, shape as an inverted, thick-walled U, especially dorsal portion above cercal cavity, becoming gradually narrower toward ventral apices of arms, in lateral view (Fig. 27) more or less rectangular with height about twice width, dorsal margin bluntly rounded, slightly sloping ventrad posteriorly, widest subventrally; cercus in posterior view (Fig. 26) elongate, more or less oval, pointed dorsomedially, rounded ventrally, in lateral view (Fig. 27) lunate; presurstylus symmetrical, in posterior view (Fig. 26) rounded ventrolaterally, pointed dorsomedially, point oriented dorsally, this portion more densely setulose, especially medial and dorsal margins, in lateral view (Fig. 27) irregularly rectangular, dorsal margin with 2 pointed extensions, between pointed extensions deeply emarginate, ventral margin irregularly convex; postsurstylus symmetrical, in lateral view (Fig. 30), elongate, moderately narrow lateral margins sinuous, each postsurstylus bearing a rod-like process extended subapically, process pointed apically; subepandrial plate in ventral view moderately broadly U-shaped, basal portion nearly flat; aedeagus in lateral view (Fig. 30) somewhat quadrate on basal half, apical portion as a narrow, clavate process, in ventral view (Fig. 29) elongate, moderately narrow, basally emarginate medially, with pointed, ventrally directed extensions laterally, thereafter ventrally tapered to acute point, lateral margins of apical portion sinuous; phallapodeme in lateral view (Fig. 30) triangular, in ventral view (Fig. 29) elongate, slender, with basal and subapical short crossbars; pregonite in lateral view (Fig. 30) small, rod-like, bearing 2 setulae apically; hypandrium in ventral view (Fig. 29) robustly U-shaped, especially anteriorly thickened, arms extended posteriorly, deeply emarginate posteromedially; in lateral view (Fig. 30) deeply pocket-like, more or less rectangular, posterior margin shallowly concave on basal portion, base oriented posterior, narrowly pointed.

Type material. The holotype male is labeled “ Brasilien Nova Teutonia[,] 27°11' B, 52°23'L[,] Fritz Plaumann 300–500 m [,] VI 1970 [the label has a black submargin]/ Holotype ♂ Mimapsilopa plaumanni Mathis, Costa, & Marinoni MZUSP [red]). The holotype is double mounted (minuten in card board base), is in good condition (abdomen removed and dissected, some setae of the head missing) and is deposited in MZUSP. Two paratypes (1♂, 2♀; MZUSP) bear the same label data as the holotype.

Type locality. Brazil. Santa Catarina: Nova Teutônia (27°11'S, 52°23'W; 3–500 m).

Distribution (Fig. 52). Neotropical: Argentina (Tucumán), Brazil (Santa Catarina).

Etymology. The species epithet, plaumanni, is a Latin genitive patronym to honor Fritz Plaumann (deceased), collector extraordinaire, whose carefully prepared specimens have contributed significantly to the study of Brazil’s insect biodiversity.

Remarks. This species is closely related to M. schildi (Cresson), also of the metatarsata group, as evidenced by the similarly shaped structures of the male terminalia. Both species have the dorsal portion of the epandrium very thickly developed and the medial margin of the presurstylus is minutely and densely setulose. The cercus of M. plaumanni is elongated, however, unlike the stout, short cercus of M. schildi, and the shapes of the presurstyli are also diagnostic, in both lateral and posterior views (see Figs. 26 and 27).