Dytomyia flavicaudata, Ya., 2021

Ya., Igor, 2021, Discovery of Dytomyia Bickel (Diptera: Dolichopodidae) on the African continent with description of a new peculiar species from Kenya, Israel Journal of Entomology (Oxford, England) 51 (6), pp. 85-91 : 87-89

Dytomyia flavicaudata n. sp.

( Figs 1A–F)

LSID: urn:lsid:zoobank.org:act:58036DC8-A60B-4DA3-85C7-887DFCFA8637 .

Etymology: From Latin flavus (yellow) and cauda (tail), in the reference to the yellow colour of the hypopygium.

Diagnosis: Dytomyia flavicaudata n. sp. differs from all other species of the genus mostly in its yellow abdomen and entirely yellow hypopygium. The abdomen and hypopygium are entirely brown to green-black, with metallic reflections in other Afrotropical species. The outer lobe of the male cercus in the new species is unusually long and thin, 1.7× as long as epandrium, whereas most other species of the genus (except for D. lutescens ) have a short cercus, not longer than the epandrium. Males of D. lutescens also have a long cercus, 2× as long as epandrium, but its outer lobe bears a large spade-like ventral projection in basal ⅓.

Description: Male ( Fig. 1A). Head ( Fig. 1B): Frons shining greenish blue, densely covered with short white hairs; 1 vertical bristle (broken) and 1 short white postvertical seta; postocular setae white, uniserial; ventral postcranium covered with long irregular white hairs; face and clypeus densely covered with short white hairs; face broad, 1.3× as high as wide under antennae, inconspicuously narrowed downward; clypeus as high as wide, separated from eyes; antenna with scape and pedicel small, simple, light yellow; pedicel with ring of short white setae and 1 short black dorsal bristle; postpedicel broken; palpus yellow with white hairs and 2 yellow bristles; proboscis yellow with white hairs.

Thorax: Metallic bluish green with black bristles; metepimeron yellow; mesonotum and scutellum weakly pollinose, pleura densely white pollinose; 4 strong dorsocentral bristles decreasing in length anteriorly; acrostichals inconspicuous; scutellum with 2 strong bristles.

Legs including coxae yellow, segments 4 and 5 of hind tarsus brown (mid legs broken off); fore and mid coxae with white hairs and 2–4 white subapical bristles; hind coxa with 1 yellow seta at base and 2 short hairs; fore and mid femora without remarkable setae or hairs; fore tibia with 1 brown posterior seta at middle, 2× as long as diameter of tibia; fore basitarsus slightly thickened, with ventral pad of short white hairs along entire length; hind tibia with several short light dorsal setae, 1 black apical seta dorsally; hind basitarsus with short basoventral seta; tarsomeres 4–5 slightly widened and flattened; tarsomere 5 2× as long as wide ( Fig. 1C); femur, tibia and tarsomere (from first to fifth) lengths (mm): fore leg: 1.36/1.24/0.84/0.36/ 0.19/0.16/0.16, hind leg: 1.77/2.06/0.93/0.65/0.37/0.2/0.17.

Wing ( Fig. 1D): Widest at middle, almost hyaline, veins yellow-brown; costa with simple setulae; R 4+5 gently curved to M 1 in apical third; M 1+2 almost straight; M 1 with strong elbow, forming nearly right angle with M 1+2; ratio of parts of costa between R 2+3 and R 4+5 to those between R 4+5 and M 1, 6/1; crossvein dm–m straight; ratio of crossvein dm–m to apical part of M 1+2 (fork-handle) to apical part of M 4, 0.38/0.56/0.23; anal vein not reaching wing margin; anal lobe well developed and alula small; anal angle acute; lower calypter yellow with white cilia; haltere light yellow.

Abdomen: Mostly yellow with white hairs and short brown marginal setae; tergites 5 and 6 mostly shining blue-green; pregenital segments combined at most 2× as long as thorax; segment 7 short, concealed; hypopygium massive and globular, yellow; hypopygial foramen basal in position and covered by cap-like sternum 8 ( Fig. 1E); surstylus broad, flattened and fused to epandrium, with deep incision distally; outer lobe of cercus long and narrow, light yellow, glabrous on middle ⅓, with several ventral setae on basal ⅓ and ventral rows of brown setae on distal ⅓ ( Fig. 1F); adjacent cercal lobe slightly curved, half as long as outer lobe, with inner pad of microscopic hairs; short ventral section of cercus arising basally and freely articulated with main cercal body, consisting of free outer stick-shaped arm covered with setae and short subtriangular glabrous arm, which fused with the same arm of another cercus; 2 epandrial lobes long, finger-like, each with 1 long and 1 short apical setae; 1 short epandrial seta.