Small slender yellowish to brown flies, ranging in length from about 2.0 to 3.8 mm. Head as wide as or wider than thorax; eyes broadly separatated in both sexes. Wing rather long, slender, and somewhat pointed, with characteristic venation that shows sexual dimorphism; in male A1+CuA2 terminating in hind margin of wing; in female A1+CuA2 joining CuA1 and terminating in wing margin as A1+CuA2+CuA1.