Psilota occidua Young, 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 : 66

Psilota occidua Young sp. nov.

(Species plate: Fig. 28 ; Map: Fig. 61A )

Diagnosis: Metallic blue species with frons pale pilose, pleuron shiny and white pilose. Hind femur with a distinct rounded apicoventral setulose carina. Hind tibia simple. Tergite 4 almost entirely black pilose, with only posterior rim white pilose. Sternite 1 pollinose. Body length: 8.4 mm.

Description: MALE: Unknown.

FEMALE: Head: Head black, face pale pollinose. Face pale pilose, frons mixed dark and pale pilose, with a cluster of dark pile just above the antenna, vertex black pilose. Antenna mostly orange, dull brown dorsally on postpedicel. Eye pale pilose. Thorax: Thorax black, with greenish tints. Coxae, trochanters, and femora mostly black, with an apico-anterior stripe on the pro and mesofemora, and the apex of the metafemur orange. Tibiae and basotarsi orange, apical four tarsomeres progressively darker. Hind femur with a distinct rounded apicoventral setulose carina. Hind tibia simple, with no basoventral spur. Pleuron shining, pollinosity free. Pile on scutum and scutellum mixed dark and pale. Scutum mostly pale pilose, with some dark pile on dorsal half of the anepisternum and anepimeron. Wing colourless, with cells c, bm mostly bare. Cells cua, r, r 4+5, r 2+3, and dm with bare areas basally. Alula completely microtrichose. Halter dark brown. Calypter pale, with a dark brown border. Pile at edge of upper calypter pale, pile at edge of lower calypter dark brown. Abdomen: Abdomen metallic blueish-green. Tergite 2 pale pilose, tergite 3 pale pilose laterally and dark pilose medially, tergite 4 almost entirely dark pilose, with only the posterior margin pale pilose. Sternite 1 pollinose, sternites 2–4 shining. All sternites pale pilose. Genitalia: male unknown.

Etymology: The specific epithet occidua is derived from the Latin “occidens”, which means “Western”. This refers to the fact that the only known specimen of this species is from Western Australia.

Specimens examined: HOLOTYPE: AUSTRALIA: Western Australia: D’Entrecasteaux National Park: Deeside Coast Road , Malaise trap, 81m, 5–14.xi.2003, -34.77675 116.315667, C. Lambkin, J. Recsei, J. Hamilton ANIC Database No. 29 035751 (1♀, ANIC).

Discussion: This species is known from a single specimen collected in Western Australia. Although no male has been collected, the holotype was successfully DNA barcoded, so if a male is collected in the future it can be confidently matched to the holotype using DNA evidence. The barcode data extracted from the holotype is publicly available on the BOLD website (process ID: SYCNC760-18) and on Genbank ( MK073144 ), as detailed above in the Materials and Methods section.

Figures

FIGURE 28. P. occidua sp. nov., A) female dorsal habitus, B) female anterolateral face, C) female lateral habitus. Scale bar =1 mm.

FIGURE 61. Known range of A) P. occidua sp. nov.; B) P. pollinosa sp. nov.