Hydrellia simplex, Júnior, Francisco De Assis Rodrigues, Mathis, Wayne Nielsen & Couri, Márcia Souto, 2014

Júnior, Francisco De Assis Rodrigues, Mathis, Wayne Nielsen & Couri, Márcia Souto, 2014, Hydrellia Robineau-Desvoidy (Diptera: Ephydridae) from Brazil with an emphasis on the faunas from the states of Parana and Rio de Janeiro, Zootaxa 3753 (6), pp. 501-541 : 531-534

Hydrellia simplex sp. nov.

(Figs.: 20.4, 24.1–24.8, 25.1–25.4 and 26)

Diagnosis. Body length of male 2.18–2.33 mm, female 2.17–2.77 mm; head broader than high; frons broader than high, frontal vitta golden brown; fronto-orbital plate darker, usually black; ocellar setae present, three times shorter than pseudopostocellar setae; both proclinate and reclinate fronto-orbital setae present; antennae mostly grayish brown to black; pedicel with 1 distinct spine like setae dorsally and 1 well-developed setula behind this; 8–10 aristal rays; face narrow, silver to golden yellow, in lateral view with a distinct mid dorsal carina, antennal groove distinct; maxillary palpus yellow to pale yellow (fig. 20.4); mesonotum silvery brown to golden brown over black; well-developed dorsocentral setae 0+1; pleural areas below notopleuron bluish gray (fig. 20.4); postpronotum mostly silvery gray; notopleuron transitional, tannish; legs mostly silvery gray; joints yellow to dark orange yellow (fig. 20.4); forebasitarsomere darkened, grayish brown microtomentose medioapically, orange yellow basally; mid and hind tarsi yellow to dark orange yellow becoming grayish brown to black apically; ctenidial setae along anteroventral margin of forefemur well developed; surstylus in ventral view longer than wide, with a deep medial cleft and a smaller lateral cleft, lateral process slightly bent laterally (figs. 24.1 and 24.6), in lateral view, with a small keel-like carina in posterior margin apically (fig. 24.7); sternite 5 rounded anteriorly, microsetulose, each lateral arm deeply cleft, forming a medial, narrow, elongate process bearing apical setulae (figs. 24.1 and 24.2).

Description. Head: almost broader than high; frons broader than high; frontal vitta golden brown; frontoorbital plate darker, usually black; ocellar setae present, three times shorter than pseudopostocellar setae; both proclinate and reclinate fronto-orbital setae present, with a third smaller setula between them, posterior frontoorbital seta 1.5–2.0 times as long as anterior seta; antennae mostly grayish brown to black; pedicel with 1 distinct spine like setae dorsally, 1 well-developed setula behind this and 2 ventral hair-like setulae; first flagellomere with inconspicuous dorsomedial micropubescence; 8–10 aristal rays; face narrow, silver to golden yellow, in lateral view with a distinct mid dorsal carina, antennal groove distinct; 5–7 primary facial setae and 1 minute shallowly declinate dorsal secondary facial setula; lunule usually concolorous with face; gena, postgena and occiput silvery gray (fig. 20.4), genal groove black; 1 genal seta; usually with 1 well-developed postgenal setula; maxillary palpus yellow to pale yellow, spatulate, with 3 setulae; epistomal ratio: 1.77–1.87; mesofacial ratio: 2.91–2.94; vertex ratio: 6.99–7.40; eye-to-gena ratio: 7.14–7.30; head ratio: 1.24–1.27.

Thorax: mesonotum silvery brown to golden brown over black, sometimes with a bluish band along of dorsocentral and acrostichal rows; well-developed dorsocentral setae 0+1; 3 scutellar setae, mid pair reduced; 1 postpronotal seta; 1 mesokatepisternal seta; pleural areas below notopleuron bluish gray (fig. 20.4); postpronotum mostly silvery gray; notopleuron transitional, tannish. Wings (fig. 20.4): length 2.37–2.54 mm; hyaline with dark yellow venation; knob of halter fluorescent yellow, stem dark yellow; costal sections indices: II/I: 2.62–2.78; III/ IV: 2.65–3.09; V/IV: 3.37–3.78; vein M ratio: 3.92–4.02. Legs (fig. 20.4): mostly silvery gray; joints yellow to dark orange yellow; forebasitarsomere darkened, grayish brown microtomentose medioapically, orange yellow basally; mid and hind tarsi yellow to dark orange yellow becoming grayish brown to black apically; ctenidial setae along anteroventral margin of forefemur well developed; mid tibiae with a weakly developed tibiotarsal ctenidium; posterior tibiotarsal joint without weakly developed ctenidium.

Abdomen: tergites grayish brown over black dorsally, anterodorsal corners of syntergite 1+2 to tergite 5 grayish brown microtomentose when in lateral view (fig. 20.4). Male terminalia: surstylus in ventral view longer than wide, with a deep medial cleft and a smaller lateral cleft, lateral process slightly bent laterally (figs. 24.1 and 24.7), in lateral view, with a small keel-like carina in posterior margin apically, usually possible to see in nondissected specimens (figs 24.8); sternite 5 rounded anteriorly, microsetulose, each lateral arm deeply cleft, forming a medial, narrow, elongate process bearing apical setulae (figs. 24.1 and 24.2); postsurstylus broad (figs. 24.1 and 24.2); postgonite straight; pregonite long, slightly bent medially, bifurcated, each arm bearing 1 setula (figs. 24.1 and 24.2); aedeagus in ventral view fusiform (fig. 24.3); distiphallus long, membranous; epandrium broad, forming an inverted U (fig. 24.1). Female terminalia: tergites 3–4 subequal, tergite 5 about 1.5 longer than tergite 4; tergite 6 twice length of tergite 7 (fig. 25.2), tergites 7 and 8 subequal; tergite 8 forming an inverted U around cerci; cerci in lateral view reniform; sternites 3–5 roundly rectangular, progressively larger; sternites 6–7 roundly quadrate, tergite 7 slightly shorter (fig. 25.1); tergite 8 rounded truncate anteriorly and concave posteriorly, bent dorsally (fig. 25.1); hypoproct higher than wide, projected between cerci, roundly triangular with 2 small lobes basally and 2–4 apical setulae (fig. 25.1); ventral receptacle with a cap cupuliform, slightly higher than wide, extended process Jshaped in lateral view (fig. 25.3).

Egg (fig. 25.4): fusiform; chorion corrugate, with perpendicular striae; micropylar end rounded.

Material examined. Holotype male ( MNRJ): “ Brazil, Paraná, Parque Iguaçú (25°33.4'S, 49°13.6'W; 880 m), 9.Nov.2010; D. & W. N. Mathis”. Paratypes: Brazil. Amazonas, Paraná da Cigana. Parintins (2°37'42''S, 56°44'9''W *), XI.1969; Exp. Perm. Amaz. (2 male, 1 female; MZUSP). Paraná, Matinhos (25°46.4'S, 48°30.8'W; 3 m), 30.I.2010, D. and W. N. Mathis (1 female; USNM). Paraná, Parque Iguaçú (25°33.4'S, 49°13.6'W; 880 m), 1.II–9.XI.2010, D. and W. N. Mathis (9 male, 4 female; MNRJ, USNM). Paraná, Castro (8 Km N; 24°45.3'S, 49°58.9'W; 1010 m), 24.XII.2009, 1.I.2010, D. and W. N. Mathis (6 male; USNM). Paraná, Curitiba, Universidade Federal do Paraná, Reserva Biológica (25°26.9'S, 49°14'W; 915 m), 18.I–05.XI.2010, D. and W. N. Mathis (5 male, 1 female; USNM). Paraná, Bocaiúva do Sul (25°14.9'S, 49° 8.9'W; 890 m), 2–4.XI.2010, D. and W. N. Mathis (1 male, 5 female; USNM). Paraná, Prainha (S Matinhos; 25°51.2'S, 48°33.6'; beach), 15.XI.2010, D. and W. N. Mathis (1 female; USNM). Rio de Janeiro, Floresta da Tijuca (22°57'27.60''S, 43°16'26.08''W; 507 m), 17.XI.2011; F. A. Rodrigues Jr. (2 female; MNRJ). Rio de Janeiro, Gávea (22°58'32''S, 43°14'5''W *), 18.III– 29.VI.1937; H. S. Lopes (1 male, 2 female; CEIOC). Rio de Janeiro, Ilha da Marambaia (23°03'55.50''S, 43°52'50.94''W, 4 m), 14.V.2011, M. A. Schneider & F. A. Rodrigues Jr. (1 male; 2 female; MNRJ). Rio de Janeiro, Jardim Botânico (22°57'43'', 43°13'23''W *), VI.1934; H. S. Lopes (1 male; CEIOC).

Distribution. Neotropical: Brazil (Amazonas, Paraná and Rio de Janeiro).

Etymology. The specific epithet, simplex , refers to the fact that this is a widely distributed and easily found species in Brazil.

Notes. Hydrellia simplex sp. nov. belongs to the griseola species group, as do H. vilelai sp. nov. and H. schneiderae sp. nov. It is morphologically very similar to H. wirthi and H. vilelai sp. nov. Externally, we cannot consistently distinguish among these species and rely primarily on structures of the male and female terminalia to differentiate them.