Hydrellia cavator 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 : 512-514

Hydrellia cavator Deonier 1971

(Figs.: 7 and 8.1–8.7)

Hydrellia cavator Deonier 1971: 49 (description of male and female). Holotype female, AMNH. Type-locality: United States, Lake worth, Florida (26°36'57''N, 80°3'25''W *); Deonier 1998: 98 –100 (redescription); Mathis & Zatwarnicki 1995: 67 (world catalog).

Diagnosis. Body length of male 1.63–1.70 mm *; female 2.13–2.24 mm *; frons broader than high; ocellar setae present, twice shorter than pseudopostocellar setae; both proclinate and reclinate fronto-orbital setae present; frons golden brown; fronto-orbital plate usually concolorous with frontal vitta, sometimes slightly darker; face narrow, in lateral view nearly vertical, only slightly convex, golden brown, antennal groove indistinct; first flagellomere orange yellow ventrobasally, dark brown dorsoapically, with inconspicuous dorsomedial micropubescence; 4–6 aristal rays; mesonotum grayish brown, subshiny; well-developed dorsocentral setae 0+1; pleurae golden brown until ventral margin of notopleuron, other pleural areas silvery gray; ctenidial setae along anteroventral margin of forefemur weakly developed; tarsi mainly pale to orange yellow; anterolateral margin of sternite 5 truncate, posterior margin deeply concave, irregularly setose (figs. 8.1 and 8.2); anterior margin of surstylus smoothly convex, posterior margin shallowly concave, surstylus with two rows of setulae medially (figs. 8.1 and 8.7); phallapodeme in ventral view Y-shaped anteriorly, with a thin membrane between the process, slightly broad mediobasally, posterior margin truncate (fig. 8.5).

Description. Head: almost as broad as high; frons broader than high; ocellar setae present, twice shorter than pseudopostocellar setae; both proclinate and reclinate fronto-orbital setae present, with a third smaller setula between them; frons golden brown; fronto-orbital plate usually concolorous with frontal vitta, sometimes slightly darker; face narrow, in lateral view nearly vertical, only slightly convex, golden brown; antennal groove indistinct; lunule concolorous with face; parafacial usually concolorous with face, sometimes darker; 4–5 primary facial setae, with 1 declinate dorsal secondary facial setula; scape and pedicel dark brown to dark grayish brown; pedicel with 1 distinct spine like setae dorsally and 1 well-developed setula behind this, 2–3 ventral hair like setulae; first flagellomere usually orange yellow ventrobasally, dark brown dorsoapically, with inconspicuous dorsomedial micropubescence; 4–6 aristal rays; 1 well-developed genal seta; postgena sometimes bearing 1 well-developed posterior seta; gena, postgena and lower occiput silvery gray, dorsal occiput dark brown; maxillary palpus orange yellow, bladelike, bearing 3 setulae; epistomal ratio: 1.43–1.58; mesofacial ratio: 2.07–2.47; vertex ratio: 4.30– 4.88; eye-to-gena ratio: 7.65–8.14; head ratio: 1.11–1.20.

Thorax: mesonotum grayish brown, subshiny; well-developed dorsocentral setae 0+1; 3 scutellar setae, mid pair weakly developed; 1 postpronotal seta; 1 mesokatepisternal seta; pleurae golden brown until ventral margin of notopleuron, other pleural areas silvery gray; anepisternum slightly golden brown microtomentose mid posteriorly. Wings: length 1.83–2.56 mm; hyaline with dark brown venation; knob of halter pale yellow, stem dark brown; costal sections indices: II/I: 2.01–2.33; III/IV: 3.47–3.86; V/IV: 3.88–4.35; vein M ratio: 4.14–4.36. Legs: mainly silvery gray; joints brownish; ctenidial setae along anteroventral margin of forefemur weakly developed; mid tibiotarsal ctenidium present but weakly developed; tarsi mainly pale to orange yellow, becoming dark brown from tarsomere 3, apical tarsomere dark grayish brown.

Abdomen: dark grayish brown dorsally, silvery gray in lateral and ventral views. Male terminalia: anterolateral margin of sternite 5 truncate, posterior margin deeply concave, irregularly setose (figs. 8.1 and 8.2); postgonite bent anterolaterally (figs. 8.1 and 8.2); pregonite long, straight, slightly bent medially (figs. 8.1 and 8.2); postsurstylus broad basally becoming thin medioapically (figs. 8.1 and 8.2); aedeagus fusiform in ventral view (fig. 8.3); anterior margin of surstylus smoothly convex, posterior margin shallowly concave, surstylus with two rows of setulae medially (figs. 8.1 and 8.7); phallapodeme in ventral view Y-shaped anteriorly, with a thin membrane between the process, slightly broad mediobasally, posterior margin truncate (fig. 8.5), in lateral view L-shaped (fig. 8.6); epandrium narrow (fig. 8.1). Female terminalia: tergites 3–5 subequal; tergite 6 slightly shorter than fifth; tergites 7–8 mostly retracted within sixth; eighth tergite forming an inverted U around cerci; cerci in lateral view ovoid with a short petiole; sternites roundly rectangular; sternites 3–5 subequal in size; sternite 6 twice longer than seventh; tergite 8 1.5 times shorter than seventh; hypoproct well developed, longer than wide, roundly triangular, uniformly setulose, projecting to apical third of cerci; ventral receptacle with a cap cupuliform, about 1.5 times longer than wide, extended process J-shaped in lateral view.

Material examined. Brazil: Rio de Janeiro, Ilha da Marambaia (23°03’55.50”S 43°52’50.94”W, 4 m), 11.VI.2011; M. A. Schneider & F. A. Rodrigues Jr. (1 male, 7 female; MNRJ).

Distribution. Nearctic: United States (Florida). Neotropical: Brazil (Rio de Janeiro).

Notes. This species was described from the United State of America, and is for the first time recorded from the Neotropical region. This species is morphologically very similar to H. vulgaris Cresson and H. schneiderae sp. nov., but can be distinguished by the coloration of the forebasitarsomere, dark brown to black in both last two species and pale yellow to orange in H. cavator Deonier , this in addition to the male and female terminalia morphology.