Peradon notialus Reemer

Reemer, Menno, Skevington, Jeffrey H. & Kelso, Scott, 2019, Revision of the Neotropical hoverfly genus Peradon Reemer (Diptera, Syrphidae, Microdontinae), ZooKeys 896, pp. 1-93 : 1

Peradon notialus Reemer sp. nov. Figs 82 , 83 , 94 , 146 , 147 , 222-227 , 279

Type material.

Holotype. Argentina • 1 ♂, holotype of Peradon notialus sp. nov.; Prov. Tucumán, N307 betw. Monteros and Tafi del Valle nr. km 16; 27°05.70'S, 65°36.93'W; 560 m a.s.l.; 13 Oct. 2003; S.M. Blank & C. Kutzscher; CSCA. Label 1: "Argentina: Prov. Tucumán, / N307 betw. Monteros and / Tafi del Valle nr km 16 / 27°05.70'S, 65°36.93'W / 560 m alt., 13.10.2003, / S.M. Blank & C. Kutzscher".

Paratypes. Brazil • 1 ♂, paratype of Peradon notialus sp. nov.; Rio Grande do Sul, 60 km NE de Bagé, Palmas; 30°59'S, 53°37'W; 270 m a.s.l.; 17 Nov. 2007; E. & J. Almeida leg.; UPFR • 1 ♀; same data as previous paratype except leg. D. Parizotto.

Description

(based on holotype). Adult male. Body size: 6 mm.

Head. Face occupying 0.48 of head width in frontal view; black; white pile. Gena black; white pilosity. Lateral oral margin weakly produced; black; white pilosity. Frons and vertex black; black pile. Occiput black; white pilosity. Eye bare. Antennal fossa approx. as wide as high. Antenna brown. Length ratio of scape:basoflagellomere approximately 1:1. Basoflagellomere parallel-sided with rounded apex. Arista slender, ca. 2/3 of length of basoflagellomere.

Thorax. Mesoscutum dull black; short, pale yellowish pile, except for narrow fascia of silvery white pile across mesoscutum. Postpronotum brown; bare. Postalar callus brown; yellow pilosity. Scutellum black with faint metallic shine; yellowish white pilosity; with two apical calcars of ca. 1/4 of length of scutellum, with mutual distance slightly more than 1/2 length of scutellum. Pleura blackish brown. Anterior and posterior part of anepisternum separated by deep sulcus; white pilosity anteriorly and posteriorly, with wide bare area in between. Anepimeron entirely whitish pilosity. Katepisternum white pile dorsally, with very small patch of pile ventrally. Other pleurae bare (except for microtrichiae). Calypter and halter yellow.

Wing. Hyaline, except cells bc, c, sc, and vena spuria yellow. Wing microtrichose, except cell bc largely bare. Legs: brownish black; white pilose, except tarsi ventrally golden yellow pile.

Abdomen. Elongate, widest at apex of tergite 2; blackish brown, except posterior margin of tergite 4 yellow; tergite 1 white pile; tergite 3 with short black pilosity, except longer golden yellow pilosity along lateral and posterior margins; tergite 4 golden yellow pilose, with pile more dense laterally and medially, very sparse in between. Sternites brown; white pilosity, except sternite 1 bare. Genitalia as in Fig. 279 .

Female As male, except for following differences. Body length 7.5 mm. Length ratio of scape:basoflagellomere approximately 1:1.1. Yellow wing colouration more extensive, including cell br entirely, most of bm, a small anterior part of cup, median parts of r4+5 and apex of wing. Pilosity of tergite 5 more or less like that of tergite 4 in the male, except there is a narrow median bare vitta.

Diagnosis.

Body length: male 6-8.5 mm, female 7.5 mm. This is the only species of Peradon in which the basoflagellomere is (slightly) shorter than the scape, and also one of the few with a fully microtrichose alula (this character is only shared with P. manni and P. niger , which have largely blackish wings and lack the golden pile on tergites 4 and 5).

Distribution.

The species is known from Tucumán province (Argentina) and the Brazilian state Rio Grande do Sul.

Etymology.

The specific epithet is an adjective derived from the Latin notialis, meaning southern, and refers to the distribution of this species in southern parts of South America.

Figures

Figures 74 - 85. Wings of Peradon species of the flavofascium - group 74 P. flavofascium ♂ holotype 75 P. flavofascium ♀ 76 P. surinamensis ♂ holotype 77 P. surinamensis ♀ Suriname RMNH 78 P. aurigaster ♂ holotype 79 P. aurigaster ♀ Peru CNC 80 P. ballux ♂ holotype 81 P. brevis ♂ holotype 82 P. notialus ♂ holotype 83 P. notialus ♀ paratype 84 P. chrysopygus ♂ Costa Rica RMNH 85 P. chrysopygus ♀ Belize MZH.

Figures 90 - 96. 90, 91 Scutellum: 90 P. flavofascium male (holotype) 91 P. surinamensis male (holotype) 92 - 96 Mesonotum: 92 P. flavofascium female (Brazil MZUSP) 93 P. surinamensis female (paratype) 94 P. notialus male (holotype) 95 P. ballux male (holotype) 96 P. brevis male (holotype).

Figures 143 - 148. Dorsal habitus of Peradon species (flavofascium group) 143 P. aurigaster ♂ Bolivia RMNH 144 P. aurigaster ♀ Peru RMNH 145 P. ballux ♂ holotype 146 P. notialus ♂ holotype 147 P. notialus ♀ paratype 148 P. brevis ♂ holotype. Scale bar: 10 mm.

Figures 222 - 227. 222 - 224 Peradon notialus male, holotype: 222 habitus lateral 223 head frontal 224 head lateral 225 - 227 Peradon notialus female, holotype 225 habitus lateral 226 head frontal 227 head lateral.

Figures 274 - 279. Male genitalia of Peradon species 274 P. luridescens Suriname RMNH 275 P. angustiventris Suriname RMNH 276 P. palpator holotype 277 P. flavofascium holotype 278 P. surinamensis holotype 279 P. notialus holotype.