The structure of 180 degrees supernumerary limbs and a hypothesis of their formation.
D000558:Ambystoma mexicanum; D000818:Animals; D002356:Cartilage / Q000033:anatomy & histology; D005121:Extremities / Q000033:anatomy & histology* / Q000502:physiology; D009132:Muscles / Q000033:anatomy & histology; D012038:Regeneration; D012399:Rotation