Hydrellia agitator Deonier 1971

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 : 504-506

Hydrellia agitator Deonier 1971

(Figs.: 1.1–1.7 and 2)

Hydrellia agitator Deonier, 1971: 36 –37 (description of male and female). Holotype male, USNM 70525. Type-locality: United States, Florida, Port Saint Joe Beach, Gulf County (29°48'42''N, 85°18'10''W *); Deonier 1998: 47 –49 (redescription); Mathis & Zatwarnicki 1995: 61 (world catalog).

Diagnosis. Body length of male 1.70–1.79 mm *, female 1.79–2.21 mm *.Head much broader than high; ocellar setae present, three times shorter than pseudopostocellar; pedicel with 0–1 well-developed setae dorsally; first flagellomere with dense, short, dark brown dorsomedial micropubescence; 7 aristal rays; well-developed dorsocentral setae 1+1; mesonotum densely metallic green microtomentose over black, comparatively more metallic green than H. tibialis ; pleurae silvery gray, except for notopleuron, contrasting with brownish notum and notopleuron, as in H. calverti ; mid and hind tibiae in both sexes enlarged; mid and hind basitarsomeres orangeyellow; abdomen dark grayish brown with metallic green reflections; sternite 5 deeply concave and congruent with distiphallus (figs. 1.1 and 1.2); distiphallus broad apically, striate, protruding far beyond surstylus (fig. 1.3); surstylus trapezoidal, slightly concave in anterior margin (fig. 1.7).

Description. Head: much broader than high; frons broader than high, densely microtomentose, dark brown to black; fronto-orbital plate usually darker; ocellar setae present, three times shorter than pseudopostocellar; both proclinate and reclinate fronto-orbital setae present, with a third smaller setula between them; antenna mostly dark brown to black; pedicel with 0–1 well-developed setae dorsally and 1 ventral hair like setula; first flagellomere with dense, short, dark brown dorsomedial micropubescence; 7 aristal rays; face narrow, silver, bearing 6 primary facial setae, usually with 1 declinate dorsal secondary facial setula; in lateral view nearly vertical but with low, rounded, ventromedial carina and shallow but distinct antennal grooves; lunule concolorous with face; parafacial narrow, concolorous with face; gena and postgena grayish brown, occiput darker; genal groove black; 1 genal seta; maxillary palpus dark brown to black, cleaver shaped; epistomal ratio: 1.55–1.58; mesofacial ratio: 2.32–2.45; vertex ratio: 5.75–5.86; eye-to-gena ratio: 5.67–6.00; head ratio: 1.40–1.43.

Thorax: well-developed dorsocentral setae 1+1; 3 scutellar setae, mid pair weakly developed; 1 mesokatepisternal seta; 1 postpronotal seta; mesonotum densely microtomentose, metallic green over black; pleurae silvery gray, except for notopleuron, contrasting with brownish notum and notopleuron. Wings: length 1.81–2.01 mm; wings hyaline with dark brown venation; knob of halter yellow, stem brown; costal section indices: II/I: 1.97–2.63; III/IV: 2.91–3.37; V/IV: 3.09–4.00; vein M ratio: 2.38–2.93. Legs: dark brown, gray microtomentose, joints dark brown; ctenidial setae along anteroventral margin of forefemur weakly developed; mid and hind tibiae of both sexes enlarged; mid and hind basitarsomeres orange-yellow.

Abdomen: dark grayish brown with metallic green reflections. Male terminalia: sternite 5 deeply concave and congruent with distiphallus, posterior arms setose, with 3–4 long setae reaching surstylus anterior margin or even more (figs. 1.1 and 1.2); postsurstylus broad (figs. 1.1 and 1.2); postgonite bent anteromedially (figs. 1.1 and 1.2); pregonite long, sinuous (figs. 1.1 and 1.2); basiphallus fusiform (fig. 1.3); distiphallus broad apically, striate, protruding far beyond surstylus (fig. 1.3); both sides of phallapodeme truncate in ventral view (fig. 1.5); phallapodeme in lateral view L-shaped (fig. 1.6); surstylus trapezoidal, slightly concave in anterior margin (fig. 1.7); epandrium narrow (fig. 1.1). Female terminalia: tergite 7 twice smaller than tergite 6; tergites 7–8 mostly retracted within sixth; sternites subequal, roundly quadrate; tergite 8 microsetulose, with 1–2 long hair like setulae; ventral receptacle with a cap cupuliform, about 1.3 times longer than wide.

Material examined. Brazil: Pará, Furo do Jurupari (02°40'S, 52°59'W), X.1970; Exp. Perm. Amaz. (1 male; MZUSP). Pará, Paciência, Nhamundá River (02°12.7'S, 56°41.1'W), 16.I.1968; Exp. Perm. Amaz. (2 male, 1 female; MZUSP).

Distribution. Nearctic: United States (Florida, Georgia, Mississippi). Neotropical: Brazil (Pará).

Notes. Hydrellia agitator is recorded for the first time from the Neotropical Region. This species is morphologically very similar and can be confused with H. tibialis Cresson and H. calverti Cresson , however, they can be differentiated by the orientation of the fronto-orbital setae, all of them proclinate in H. calverti , and proclinate and reclinate in H. agitator and H. tibialis . The last two species can be distinguished by the coloration of the pleura and mid and hind basitarsomeres.