Trichocoelina obesula, Vilkamaa & Menzel, 2019

Vilkamaa, Pekka & Menzel, Frank, 2019, Re-classification of Lycoriella Frey sensu lato (Diptera, Sciaridae), with description of Trichocoelina gen. n. and twenty new species, Zootaxa 4665 (1), pp. 1-67 : 35-39

Trichocoelina obesula sp. n.

Figs 11 B , 13 A

Material studied. Holotype male. NORWAY, ‘Svalbard, Engelskelva’ [= Svalbard, Bjørnøya, river Engelskelva in the NE part of island], 74.4768°N, 19.1779°E, 30 m, 30.VII.2009, T. Ekrem (NTNU-VM 50594 and BOLD Sample ID BJ244, in NTNU-VM) . Paratypes. NORWAY, same data as holotype, 1 male (NTNU-VM 50595 and BOLD Sample ID BJ245, in NTNU-VM); ‘Svalbard, Lakselva’ [= Svalbard, Bjørnøya, river Lakselva], 74.4994°N, 18.9776°E, 15 m, 3.VIII.2009, T. Ekrem, 1 male (NTNU-VM 50605 and BOLD Sample ID BJ255, in NTNU- VM) .

Description. Male. Head. Face and antenna concolorous brown, maxillary palpus pale yellowish. Eye bridge 3 facets wide. Face with 9 setae. Clypeus with 1 seta. Maxillary palpus with 3 segments, 1 st segment as long as 3 rd segment, 2 nd segment shortest; 1 st segment with 1–3 setae, with dorsal patch of sensilla; surface of antennal flagellomeres smooth, body of 4 th antennal flagellomere 1.5–1.75x as long as wide, the neck shorter than broad, the longest setae as long as the width of flagellomere. Thorax. Brown, setae pale. Anterior pronotum with 8–9 setae. Proepisternum with 10–13 setae. Scutellum with 4 longer and some short and fine setae. Wing. Fumose. Length 1.8–2.0 mm. Width/length 0.40. Anal lobe weak. Veins distinct. c/w 0.65–0.75. R 1 /R 0.55–0.60. stM shorter than fork of M. r-m as long as bM or longer, both non-setose. Halter yellow. Legs. Yellow, coxal setae pale. Fore tibial organ forming an indistinct sparse patch in depression. Fore tibial spur longer than the tibial width. Abdomen. Pale brown, setae pale, moderately long and fine. Hypopygium ( Fig. 11 B ). Brown, as abdomen. Intergonocoxal area moderately long, with two short, triangular setose lobes. Gonocoxa broad, longer than gonostylus, medial margin basally smoothly curved, with rather long but sparse setosity. Gonostylus ( Fig. 13 A ) broad, apically slightly narrowed, strongly impressed; with short and dense setosity, a short apical tooth, a megaseta on the ventral side of apical tooth, some subapical and some medial megasetae more basally, megasetae slightly curved, long and slender; with 1 welldifferentiated whiplash seta on ventromedial margin. Tegmen broader than long, laterally slightly curved, apically straight, weakly sclerotized, aedeagal teeth not detectable in the specimens studied. Aedeagal apodeme long.

BIN. BOLD:ABA5289.

Discussion. By its gonostylus and tegmen, Trichocoelina obesula sp. n. resembles T. dispansa sp. n. and reminiscent species but differs in having the gonostylus broader and more richly setose. See under T. dispansa .

Etymology. The name is derived from the Latin word obesa , fat, referring to the broad gonostylus and gonocoxa of the species.

Figures

FIGURE 11. Hypopygium, ventral. A. Trichocoelina nefrens sp. n. (holotype). B. T. obesula sp. n. (holotype). Scale 0.1 mm.

FIGURE 13. Gonostylus, ventral. A. Trichocoelina obesula sp. n. (holotype). B. T. nefrens sp. n. (holotype). C. T. planilobata sp. n. (holotype). D. T. oricillifera sp. n. (holotype). Scale 0.1 mm.