New and Little Known Dolichopodidae from Indiana (Diptera)

Abstract

Male.-Length, 1.3 mm.; length of wing, 1.5 mm. Ground color of face dark blue, covered with grayish-white pollen. Front metallic, steel-blue, somewhat dulled with white pollen along the orbits. Lower orbital cilia white; the upper cilia are black and descend to the middle of the eye. Antennae black; third ioint rounded at apex, densely pubescent. Arista dorsal, long and tapering, pubescent, inserted at base of third joint. Palpi black, pubescent, bristly at tip. Dorsum of thorax and the scutellum blue-green, lightly dusted with whitish pollen; pleurae dulled with grayish pollen. Abdomen metallic green, the lateral portions with bronze reflections, the bristles short, black. Hypopygium small, black; outer lamellae minute, black, oval, clothed with delicate pale hairs; inner appendages yellow, directed backward. Coxae and legs yellow; all tarsi infuscated from near the tip of second joint as are also the posterior femora on upper apical portion. Fore and middle coxae with delicate pale hairs on anterior surface and a few black bristles at tip. Fore femora without noticeable bristles. Middle femora with a prominent black bristle near the base on lower edge, this bristle being nearly twice as long as the width of femora; slightly nearer to the base of middle femora is another, smaller bristle placed in line with the larger one. Hind femora with a few delicate pale hairs along lower edge and a row of black bristles on upper basal half. Fore tibiae of ordinary structure, without noticeable bristles. Middle tibiae with two prominent black bristles near the middle on anterior surface. Hind tibiae slightly thickened, bearing a peculiar black, spur-like appendage near the bisal third on inner side, the posterior edge with a row of about eight short, sharp bristles on apical half and a strong bristle on inner edge near the apex. First joint of fore tarsi bearing a row of short bristles on plantar surface. Middle and hind tarsi of plain structure. Joints of fore tarsi as 20-7-6-5-6; of mid tarsi as 23-9-7-6-6; of hind tarsi as 16-16-9-7-5. Halteres yellow, calypters yellow with black cilia.