Docosia fasciculata Polevoi, 2023

Polevoi, A. V. & Potapova, N. K., 2023, New data on the fungus gnats (Diptera: Keroplatidae, Mycetophilidae) of Yakutia with description of three new species, Far Eastern Entomologist 478, pp. 1-22 : 14-16

Docosia fasciculata Polevoi , sp. n.

https://zoobank.org/NomenclaturalActs/ 219F5214-51D5-4D05-BA69-2F6413EF180F

Figs 15–20

TYPE MATERIAL. Holotype – ♂, Russia: Yakutia, River Khotokho , middle part, 61.064° N, 113.367° E, 315 m, 15.VIII 2018, A. Burnasheva leg. [ ZISP, INS _ DIP_0001009].

DIAGNOSTIC CHARACTERS. Small species with black body, partly darkened legs and transparent wings. Resembles Docosia landrocki Lastovka et Sevcik, 2006 and D. caucasica Kurina et Kirik, 2021 by dense submedian tufts of modified setae on posteroventral margin of conocoxites ( Kurina & Kirik, 2021: Figs 2 B, 3 B ). Differs from both species by the shape of gonostylus. The latter is similar to that of D. mulleri Plassmann, 1986 ( Fig. 21 ), but lacking deep apical excision on its ventral branch. Most of the Nearctic species of Docosia are poorly documented, but as we can judge from available descriptions and illustrations ( Johannsen, 1912; Garrett, 1925; Van Duzee, 1928; Fisher, 1937; Taber, 2011, 2012, 2018) none of them is similar to new species.

DESCRIPTION. Male. Head, face and clypeus black. Three ocelli placed almost in line; lateral ocellus almost touching compound eye, separated from eye margins by less than half of their own diameter. Mouthparts black, palpi dark brown. Scape and pedicel dark brown (flagellum missing).

Thorax. Mesonotum, pleurae and scutellum black, with pale setae. Laterotergite and mediotergite bare. Haltere dark yellow.

Wing (partly missing). Length ca. 3 mm. Preserved part hyaline. Sc pale yellow, ends in R1. Radial veins and r-m dark brown.

Legs (partly missing). All coxae yellow and darkened basally. Trochanters blackish. Femora mostly yellow, fore and mid femur dark along entire ventral margin, hind femur darkened ventrally at base. Tibiae mostly yellow; fore and mid tibia darkened dorsally. Fore tarsus seem darker because of dense setae. Spur of fore and mid tibia yellow. Ratio of tibia to basitarsus for fore leg: 1.37.

Abdomen black with pale hairs.

Terminalia dark brown. Posteroventral margin of gonocoxites with short median and posterolateral processes; dense tufts of modified setae placed between them ( Figs 15, 18 ); the setae in tufts are flattened and curved apically ( Fig. 19 ). Tergite 9 slightly longer than wide; posterior margin rounded, bearing strong setae ( Fig. 16 ). Gonostylus: dorsal branch trapezoid in lateral view; ventral branch bearing two short apical spines and one subapical seta ( Figs 17, 20 ). Cercus with 13 combs of retinacula ( Figs 17, 18 ).

DISTRIBUTION. So far known only from the type locality in the South-East Yakutia

HABITAT AND BIOLOGY. Collected in herb-rich flood plain meadow. Larval biology unknown.

ETYMOLOGY. The species epithet (from Latin fasciculus – bundle, packet, bunch) refers to distinctive submedian agglomerations of modified setae.

Figures

Figs 15–21. Male terminalia of Docosia spp.: D. fasciculata sp. n. (15–20) and D. mulleri Plassmann (21). 15 – ventral view; 16 – dorsal view; 17 – lateral view; 18 – caudal view; 19 – posteroventral margin of gonocoxites, dorsocaudal view; 20, 21 – gonostylus, lateral view. Abbreviations: dbg – dorsal branch of gonostylus; mp – median process of gonocoxites; plp – posterolateral process of gonocoxites; smt – submedian tuft of modified setae; vbg – ventral branch of gonostylus. Scale bars = 0.2 mm.

Figs 2–7. Details of male terminalia of Sciophila canadensis Zaitzev. 2 – tergite 9; 3 – gonostylus, caudal view; 4 – gonostylus, lateral view; 5 – gonostylus, mesial view; 6 – aedeagal apparatus, dorsal view; 7 – aedeagal apparatus, lateral view. Scale bar = 0.2 mm.