Lasiopogon akaishii Hradský

(Figs 7 & 8)

Lasiopogon akaishii Hradský, 1981: 179

Small flies, 7–10 mm, brown and gray flies. The range of color, from light brown to black, and other generalized features make determination difficult. The scutum has distinct dark brown paramedian stripes which appear black when viewed from different angles. Legs dark brown, sometimes black.

Adult. Male.

Head: Face slivery gray tomentose; vertex black with medial gold pollen and long black curved hair. Mystax hair black. Genal hair long, fine, white merging into short black occipital bristles and longer proclinate black postocular bristles. Antenna black, basal segments sometimes brown; gold pollen; black bristles. Relative lengths of segments: 3>1, F2+3>2 (segment 1 = F2+3). Thorax: Scutum light and dark brown. All bristles black. Distinct broad dark brown paramedian stripes (black when viewed from different angles) extending to apex of thorax. Long black dense acrostical hair; long dense posterior dorsocentrals. Chaetotaxy with: 2 weak posthumeral, 2 presutural, 3 supraalar, and 3 postalar bristles. Scutellum gray pollinose; disc ringed with 2 rows of long black bristles. Pleura gold/gray pollinose with black and white hair and black bristles. A strong row of katatergal bristles. Posterior margin of anepisternum with sparse long black hair. Legs: Light to dark brown or black; gray pollen, black bristles, white and black hair. Posterior coxal peg absent. Femora with long dense fringes of fine white hair. All tibia with black bristles. Wings: Tinged lightly brown. Halter bright yellow. Abdomen: Male. Mostly integumental brown with thin gray apical tergite bands; white hair, black and white tomentum. Tergite 1 with 2 strong black latero-apical bristles, others white. Remaining tergites with long lateral white hair. Male genitalia (Figs 7 & 8). Epandria integumental brown/black with light gray pollen and black hair. Gonostylus dorsally broad.

Female. Similar to male except tergites with less hair.

Material examined. Kangwon Province. 8 ɗ, 7ΨΨ: 5/V/2003, Odaesan N. P., North side 500 m., 37°48’49”N, 128°42’29”E.

Field notes. Lasiopogon akaishii inhabits upland river beds and streams where it flies among mid stream boulders and banks. The asilids become active at 80°F. They are sympatric with L. rokuroi and have a similar flight period. See also Table 1 for prey and seasonality.