Crane fly leg

Tibial Spurs

Important components of the tipulid leg in identification and classification include the tibial spurs, hairs of the femor and tibia, and tarsal claws. The presumed primitive condition of crane flies showes the presence of articulating tibial spurs located at the distal apex of the femor, typically in a 1-3-3 pattern (foreleg-midleg-hindleg). The presence of tibial sprus is lost or greatly reduced in many genera and may be confused with additional hairs or bristles of the leg but may be separated by the serrated edge of the spurs. Tibial spurs are present in Tipulida, Cylindrotomidae, Pediciidae, and some Limoniinae (Limnophilinae).
The hairs of the femor and tibia may be variously produced in both number, location, or length but typically do not offer reliable characteristics for specimens identification. The genus Toxorhina, however, is separated from similar genera based on the presence of bifid hairs arrising from a shared socket.