Meoneura swifti, Stuke, 2016

Stuke, Jens-Hermann, 2016, Carnidae (Diptera) in the Canadian National Collection of Insects (Ottawa), with the description of five new species, Zootaxa 4084 (4) : -

Meoneura swifti spec. nov.

(figures 12–16)

Holotype ♂: (1) "Angel L. NEVADA / 12 mi. SW. WELLS / 11.VII.61 8400' / J. G. Chillcott"; (2) " CNC / 9315"; (3) Holotype / Meoneura swifti / spec. nov. ♂ / det. Stuke, 2015 ".

Holotype is deposited in the CNC. The specimen is glued to the needle and otherwise in good condition.

Paratypes: 4 ♂ with the same labels as holotype and the CNC numbers 9240, 9242, 9244, 9245. Two paratypes are deposited in the CNC and the other two in the PJHS.

Description of holotype (male). Length about 1.4 mm. Wing length = 1.2 mm. Head height = 0.4 mm.

Head black, anterior part of the frons very narrowly dark brown. Antenna black. Arista without pubescence. Eye with scattered short ommatrichia. Maximum eye length: maximum eye height = 0.9. Posteroventral margin of gena closest to eye margin: maximum eye height = 0.3. Frons completely slightly microtomentose. Frontal triangle reaching anteriorly 2/3 distance from anterior ocellus to frontal margin. Face slightly microtomentose. Carina narrow. Postcranium slightly microtomentose. Prementum as long as labellum and not obviously wider. Palpus brown, about half as long as the haustellum. 1 pair of distinct ocellar setae. Supralunular setae cruciate. 4 frontoorbital setae, two anterior mesoclinate, two posterior lateroclinate. 2 vertical setae. Postorbital setae parallel. 1 strong vibrissal seta. 2 supravibrissal setae, the ventral one distinctly smaller. 3 strong genal setae.

Scutum completely microtomentose and covered with very short, inconspicuous brown setulae and stronger black setae. Scutellum slightly microtomentose. Pleura slightly microtomentose. Scutum with 1 long and obvious dorsocentral seta, additional dorsocentral setae cannot be picked out from among the scattered black setulae on the scutum. 2 setae on postpronotum; 1 presutural seta; 2 notopleural setae; 1 supraalar seta; 2 postalar setae; 1 prescutellar seta; 1 apical and 1 lateral scutellar seta. 1 seta at posterior margin of anepisternum. 1 dorsal seta and 1 ventral seta on katepisternum. Wing completely covered with microtrichia. Costa without obvious setae beyond radial vein R1. Wing hyaline, veins light brown to white yellow. Base of haltere brown, knob of haltere whitish. Legs black to brown. Fore femur apically with 1 strong posteroventral seta. Hind femur apically with 1 strong anteroventral seta. Coxae without obvious setae.

Tergites without obvious depressions or setulae tufts. Abdominal pleura without setae. Segments 1–5 narrow, width of tergite 3: length of tergite 3 = 4.3. Tergites 3–5 each with a lateral seta at the posterior margin, tergite 5 in addition with a submedial long seta at the posterior margin. Sternite 5 trapezoid, about as long as broad. Sternite 5 with one pair of setae apically and one pair of setae laterally and with scattered less obvious setulae. Midventral tergite 7 distinctly developed. Protandrium short, slightly shorter than epandrium and about half length of tergite 5. The male postabdomen of the holotype is not macerated and the description of the postabdomen is based on two macerated paratypes. Epandrium with a few setulae only and no obvious setae. Maximum length dorsally in the middle of epandrium: maximum width of epandrium = 0.5. Cercus slightly projecting. Subepandrial sclerites distinctly sclerotized, elongated, fused with each other but only laterally fused with hypoproct and therefore not connected to subepandrial plate. Subepandrial sclerites without any setulae. Hypoproct slightly sclerotized; not projecting out of the epandrium; laterally with several distinct setulae that are not or hardly projecting out of the epandrium. In the middle of hypoproct a distinct small tooth. Surstylus as figs. 12 + 13 broad, with a slightly elongated and upcurved tip, anteroventrally with a keel medially. Surstylus dorsally with a few long dorsally directed setulae and on the anteroventrally keel with a few, long, medially directed setulae. No lamella. Postgonite as Fig. 15 : inconspicuous, straight, without any distinctive structure or shape. Distiphallus elongated, about as long as maximum length of epandrium. Distiphallus with dense brown setulae but without any sclerotisation.

Variability. The frons and the ocellar triangle may be brown. The ventral supravibrissal seta is missing in some specimens.

Diagnosis. Meoneura swifti is easily recognised by the surstylus that is broad, with a slightly elongated and upcurved tip (figs. 12 + 13), and with a keel at the inner side. It has dorsally a few long dorsally directed setulae and on the keel a few, long, medially directed setae. The hypoproct has laterally some strong setulae that hardly project out of the epandrium. The hypoproct is distinctly separated from the subepandrial sclerites. Meoneura swifti will key out with Sabrosky (1959) to couplet 6 due to the parallel postocellar setae, the white knob of haltere, the microtomentose scutum, and only 1 pair of distinct dorsocentral setae. Owing to the combination of only one long black posteroventral seta on the fore femur and lack of a tuft of long setulae at the postabdomen none of the alternatives at couplet 6 fit.

Etymology. This species is named in honour of the satirist Jonathan Swift (1667–1745), who demonstrated in his novel "Gulliver's Travels", that small individuals might be very important.

Distribution. So far Meoneura swifti is only known from the locus typicus in Nevada.

Figures

FIGURES 12 – 16. Meoneura swifti spec. nov. (drawn from the paratype from the locus typicus). 12. Lateral view of epandrium and surstylus. 13. Lateral view of surstylus. 14. Anterodorsal view of postabdomen excluding phallic complex. 15. Lateral view of postgonite. 16. Ventral view of sternite 4 (left) and sternite 5 (right). ce—cercus; ep—epandrium; hp: hypoproct (not fused with subepandrial sclerites); su—surstylus.