Trichocoelina incrassata sp. n.

Figs 7 A, 9 A

Material studied. Holotype male. USA, Alaska, 11 mi S Anderson Jct, Rte 3, mi 270, alder-poplar-spruce, Malaise trap, 23.VI–11.VIII.1984, S. & J. Peck (in MZH).

Description. Male. Head. Face and antenna concolorous brown, maxillary palpus pale yellowish. Eye bridge 2–3 facets wide. Face with 20 fine setae. Clypeus with 1 seta. Maxillary palpus with 3 segments, 3 rd segment longer than 1 st segment, 2 nd segment shortest; 1 st segment with 1 seta, with a dorsal patch of sensilla; surface of antennal flagellomeres smooth, body of 4 th antennal flagellomere 2.2x 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 6 setae. Proepisternum with 15 setae. Scutellum with 4 longer and some short and fine setae. Wing. Fumose. Length 2.6 mm. Width/length 0.40. Anal lobe weak. Veins distinct. c/w 0.70. R 1 /R 0.55. stM and fork of M subequal in length. r-m 2x as long as bM. bM and r-m non-setose. Halter yellow. Legs. Yellow, coxal setae pale. Fore tibial organ forming a large patch in depression. Fore tibial spur as long as the tibial width. Abdomen. Pale brown, setae pale, rather short. Hypopygium (Fig. 7 A). Brown, as abdomen. Intergonocoxal area long, with two small setose lobes. Gonocoxa broad, about as long as gonostylus, medial margin basally smoothly curved, with short sparse setosity. Gonostylus (Fig. 9 A) semiglobular, strongly impressed; subbasally with a dorsal lobe, with short setosity, with a rather long and narrow apical tooth, with numerous megasetae medially, the ventral megasetae oblique, the dorsal ones perpendicular, megasetae slender and rather short; with 1 weakly differentiated whiplash seta on ventromedial margin. Tegmen as long as broad, apically truncate, laterally with distinct shoulders, sclerotized, with an area of small aedeagal teeth. Aedeagal apodeme long and strong.

BIN. Unknown.

Discussion. By its large semigobular gonostylus with numerous short megasetae Trichocoelina incrassata sp. n. resembles most T. janetcheki (Lengersdorf, 1953) but differs in having groups of gonostylar megasetae pointing in two directions, in having shorter intergonocoxal lobes and in having the tegmen with lateral corners but without the apical process (see also under T. hians sp. n.).

Etymology. The name is Latin, incrassata, thickened, referring to the thick gonostylus.