.^RT. iJ5. NEW SPECIES OF THE GENUS DOLICHOPUS — ALDPJCH. 7 



DOLICHOPUS LONGICORNIS Stannius. 



Dolichopus longicornis Stannius, Isis, vol. 1, p. 53, 1831 (published 1838). — 

 Bkcker, Nova Acta, vol. 102, p. 170, 1921. 



Not previously reported from North America. 



Thirty-five specimens of both sexes, taken at Fairbanks, Alaska, 

 from June 29 to July 3 ; compared with European specimens in my 

 collection, determined by Doctor Kertesz. Originally described 

 from northern Europe; Frey mentions it as widespread but not 

 abundant in Finland. Redescribed for the convenience of American 

 students. In the analytical tables of Bulletin 116, the male runs to 

 couplet 2 of Group F, on page 14, where it forms a third alternative 

 "Antennae black above, yellow below including a large part of the 

 elongate third joint." 



Male. — Front green. Face shining yellow, changing to paler 

 below. Palpi yellow. Antennae very much elongated, the first 

 joint slender, the third very long with a slender point, the arista 

 attached about at the middle. Antennae black, broadly yellow below 

 including the third joint almost to its middle; the arista slightly 

 thickened be^^ond the middle but .slender at apex. Orbital cilia white 

 except a few above. 



Mesonotum and scutellum rather bright green. Pleurae green, 

 overlaid with some gray dust. Calypters with white cilia. Halteres 

 yellow. Abdomen subshining, green. Hypopygium black, green nt 

 base, the lamellae white, oval, with a sharply defined black border 

 above, becoming wider apically, the hairs along the upper border 

 longer and more erect than usual ; the apex has the usual incisions 

 and crooked bristles. 



Front coxae yellow with pale hairs on the anterior side; middle 

 coxae black except at tip, hind coxae yellow with a black spot on the 

 outer side, extending down to the bristle. Femora and tibiae 

 yellow, the hind tibiae infuscated at the tip where they are slightly 

 swollen and have on the hind side, just before the apex, a very dis- 

 tinct rounded depression; the color of the front and middle tibiae 

 is more white than usual; femora not ciliated. The middle tarsi 

 plain, brown from the tip of the first joint; hind tarsi entirely black 

 with only about three bristles. 



Wings with a grayish tinge, rather broad, with the anal angle 

 little developed ; a very pronounced thickening of the costa at the tip 

 of the first vein. 



Female. — Face broader and grayish yellow. Antennae shorter 

 than in the male, still noticeably elongated, with a very sharp point ; 

 the yellow color on the under side reaches almost to the tip and is 

 very distinct on the third joint. The cilia of the calypters may be 

 in part black. Hind tibiae scarcely at all infuscated, especially on 

 the outer side. 



Length of male 3.1 mm. ; of female 3.8 mm. 



