Head: Dark brown, sometimes slightly reddish-brown. Top of head shiny blue-black. Face slightly reddish-brown. Eyes reddish with 2 transverse lighter-colored lines across middle.
Antenna: Joints 1 and 2 dark, last joint light brown and as long as 1 and 2 combined.
Thorax: Dark brown, dull.
Wings: Base clear to slightly yellowish. Main ID: Rest of wings black with a white stripe across center and another white curved stripe just before tip.
Legs: Very long, dark brown. Front thighs (femora) black; mid thigh has base and tip lighter; hind thigh has base light, middle dark, light yellow stripe then a darker yellow to tip. Shins (tibiae) and feet dark brown, except Main ID: last segment on front feet entirely white.
Abdomen: Dark brown to black. Base constricted (wasp-like). Males have short claspers at tip, underside. Females have long ovipositor sometimes protruding, but usually curled under abdomen tip.
Similar Species: Rainieria antennaepes has light wings with faint dark tinge, somewhat triangular at center of wing, and faint dark tinge at tip. The white between the dark ‘stripes’ is much wider; T. trivittata has a much narrower, more solid white stripe. White on front feet of R. antennaepes is 2 segments long, only 1 segment on T. trivittata.
Size: 8 to 10 mm.
Habitat: Prefers moist areas like marshes.
Food: Unknown. Dung and rotting vegetation (tomatoes) by most Stilt-legged Flies.
Flight Time: June to September.
Life Cycle: Unknown. Waves front legs and said to resemble ants.
Comments: Essex County – Ojibway Prairies.
For information on synonyms, references and type specimens see next page