Tanyptera is a genus of true crane flies; its species are lustrous and black and yellow or red in color. They resemble some Ichneumonidae. Segments of the flagella of males have three outgrowths each (two lower paired and one the upper unpaired). The antennae of the females are distinctly 13-segmented. The sides of the mesothorax are glabrous. The ovipositor of the female is unusually long, the valves being only slightly shorter than the cerci. Tanyptera spp. exhibit extreme polymorphism in the body colour and body size of the sexes. The wing colors also vary from smoky-black, brown, or brownish-yellow, to transparent.