Wiedemannia londti, Sinclair, 2023

Sinclair, Bradley J., 2023, New Afrotropical species of Wiedemannia Zetterstedt (Diptera, Empididae, Clinocerinae), African Invertebrates 64 (2), pp. 139-147 : 139

Wiedemannia londti sp. nov.

Recognition.

This species is distinguished by its fully developed wings, fore coxae without erect, outstanding setae, clasping cercus with narrow base and Y-shaped apex, blade-like subepandrial sclerite and oddly shaped phallus, with reduced distiphallus.

Etymology.

It is my pleasure to name this species in honour of Jason Londt. Jason was very welcoming to me as a young visitor to the Natal Museum in 1994 and I always look forward to meeting up with him at meetings of the International Congress of Dipterology.

Description.

Male. Head: face, gena and occiput with blue pruinescence (Fig. 6 ); vertex brown. Face with faint brownish median stripe; apex of facial cleft velvety brown with bright oval blue pruinescent patches on either side of cleft in frontal view. Ocellar triangle thinly pruinescent; ocellar setae long, slender, longer than postpronotal seta; several pairs of short posterior setulae; 4 upper postocular setae strong, spine-like, not overlapping eye; lower postocular setae slender, longer. Genal width one-third height of eye. Antenna brown; scape slightly longer than pedicel; postpedicel pointed ovate; arista-like stylus short, tip blunt, about twice as long as postpedicel.

Thorax: pleura and postpronotal lobe with blue pruinescence; scutum brown with faint pair of black vittae. Antepronotum with strong, long lateral seta, nearly as long as postpronotal seta. Proepisternum with several long, pale setae. Mesonotum with 5 long dorsocentral setae, with several short setulae intermixed; several short acrostichal setulae, anterior to second dorsocentral seta; 1 postpronotal seta, with several short, dark setulae; 2 notopleural setae, lower seta weaker, shorter than upper, with numerous black setulae; 1 presutural supra-alar seta, with numerous black setulae; 1 postsutural supra-alar seta, with several setulae; 1 postalar seta; 1 pair scutellar setae, longer than dorsocentral setae, with dark marginal and discal setae and setulae. Laterotergite with cluster of pale setae.

Wing: length 4.1 mm; membrane infuscate, veins darker; basal costa seta not extending to humeral crossvein. Origin of veins M1 and M2 widely separated at end of cell dm, subequal to length of crossvein r-m. Vein CuA+CuP absent. Pterostigma not visible. Costal margin with short, strong erect setae beyond apex of Sc. Halter with dark knob; base of shaft pale brown.

Legs: coxae with blue pruinescence, concolourous with pleura; remaining leg segments dark brown. Fore femur with posteroventral row of fine setae, shorter than width of femur; fore tibia with erect ventral setae, shorter than width of tibia; otherwise uniformly covered with rows of small dark setulae; fore femur without strong preapical setae; fore coxa without erect setae; hind tibia with 2-3 pairs of strong ventral setae.

Abdomen: blue pruinescent, concolourous with thorax, covered in short setae. Tergite 8 narrow, band-like.

Terminalia (Fig. 3 ): hypandrium robust, subequal to length of epandrium. Epandrium subrectangular, produced dorsally; surstylus rounded, knob-like, with several marginal setulae. Clasping cercus arched, Y-shaped in lateral view; apical lobes, broadly rounded; inner face without peg-like setae; shorter than height of epandrium; without inner basal lobes. Subepandrial sclerite robust, blade-like, with pointed apex, projecting free beyond bases of clasping cercus. Cercal plate with 4 long setae confined to upper sclerite. Phallus straight; apex of shaft without membranous sacs, broadly rounded; apex of shaft prolonged anteroapically as slender process; distiphallus greatly reduced.

Female. Unknown.

Distribution.

This species is known only from the type locality in Malawi (Fig. 8 ).

Type material.

Holotype ♂, labelled (Fig. 7): "MALAWI Mulanje Mnt./ Likabula river valley [-15.938°, 35.519°]/ 28-30.xi.1980 1535Dc/ 1000m Stuckenberg &/ Londt Riverine/ Brachystegia woodland"; "HOLOTYPE/ Wiedemannia / Wiedemannia londti / Sinclair" [dissected] (NMSA).

Remarks.

This is the first species of Empididae to be described from Malawi. Wiedemannia londti is most similar to the odd South African species, W. hughesi with absence of erect setae on the fore coxae, enlarged hypandrium and reduction of the distiphallus.

Figures

Figure 8. Distribution of Wiedemannia in the Afrotropical Region.

Figures 4 - 6. Afrotropical Wiedemannia, holotypes 4 W. kilimanjaro sp. nov., habitus, lateral view 5 W. kilimanjaro sp. nov., labels 6 W. londti sp. nov., habitus, lateral view 7 W. londti sp. nov., labels. Scale bar: 1.0 mm (4); 0.75 mm (6).

Figures 1 - 3. Male terminalia of Afrotropical Wiedemannia 1 W. kilimanjaro sp. nov .. lateral view 2 W. kilimanjaro sp. nov., clasping cercus, anterior view 3 W. londti sp. nov., lateral view. Scale bars: 0.1 mm. Abbreviations: cerc pl - cercal plate; cl cerc - clasping cercus; epand - epandrium; hypd - hypandrium; ph - phallus; sbepand scl - subepandrial sclerite; sur - surstylus.