Psilota viridescens Young and van Steenis, 2020

Young, Andrew D., Skevington, Jeffrey H. & Steenis, Wouter Van, 2020, Revision of the Psilota Meigen, 1822 flower flies (Diptera: Syrphidae) of Australia, Zootaxa 4737 (1), pp. 1-127 : 87-89

Psilota viridescens Young and van Steenis sp. nov.

(Species plate: Fig. 36 ; Genitalia: Fig. 46 E–F; Map: Fig. 65A )

Diagnosis: Face orange, densely white pollinose, with white pile. Thorax metallic blue. Hind femur with a distinct rounded apicoventral setulose carina. Hind tibia simple. Calypter pale. Halter pale. Abdomen metallic green. Body length: 7.7–8.0 mm.

Description: MALE: Head: Head dull orange, face densely white pollinose. Face and frons white pilose, vertex black pilose. Scape and pedicel entirely orange, postpedicel brown on apical edge and orange below. Postpedicel oval, approximately 1.5 times as long as wide. Eye densely white pilose. Thorax: Thorax metallic blue. Legs almost entirely orange, with femora orange-brown. Hind femur with a distinct rounded apicoventral setulose carina. Hind tibia simple, with no basoventral spur. Pleuron shining, free of pollinosity. Pile on pleuron white. Pile on scutum and scutellum mixed black and white. Wing colourless, extensively bare on basal half. Cells c, br, bm, r 1 entirely bare. Cells cua, m 4, dm, r 4+5, and r 2+3 bare on basal half. Alula completely microtrichose. Halter pale. Calypter pale. Abdomen: Abdomen metallic green. Abdomen entirely white pilose. Sternites metallic green, and white pilose. Genitalia: Epandrium compact, about as long as tall. Cercus approximately triangular. Outer lobe of surstylus inserted at mid-height of inner lobe, curved downwards on apical third, with apex of lobe thickened and curved backwards towards base of surstylus. Inner lobe of surstylus broadening over entire length, with a large ventral excavation at midlength, rounded at apex. Phallapodeme smooth. Gonostylus slightly darkened.

FEMALE: Identical except for normal sexual dimorphism.

Etymology: The specific epithet viridescens is Latin, and means “greenish”. This is in reference to colouration of this species.

Specimens examined: HOLOTYPE: AUSTRALIA: Queensland: Sunnybank, -27.578997 153.059008, 18.IX.1927, UQIC_ Reg 94550, (1♂ QM) . PARATYPE: Queensland: Dunwich, North Stradbroke Island ; -27.500000 153.400000; 22.VIII.1958; coll. S.S. Sekhon; UQIC_ Reg 94720; (1♀, QM) .

Discussion: Nothing is known about the biology of this species.

Figures

FIGURE 36. P. viridescens sp. nov., A) male dorsal habitus, B) male anterolateral face, C) male lateral habitus. Scale bar =1 mm.

FIGURE 46. Lateral and dorsal male genitalia of A, B) P. spathistyla sp. nov.; C, D) P. spinifemur sp. nov.; E, F) P. viridescens sp. nov.; and G, H) P. viridis Macquart. Scale bar =1 mm.

FIGURE 65. Known range of A) P. viridescens sp. nov.; B) P. viridis Macquart.