tibia

[Antwiki.org] (pl. tibiae) The fourth segment of any leg, counting from the basal segment (coxa) that articulates with the thorax. At its apex the tibia frequently bears one or two tibial spurs. The tibia of the prothoracic (fore) leg is often termed the protibia, that of the mesothoracic (middle) leg the mesotibia, and that of the metathoracic (hind) leg the metatibia.