Fig 2.

Series of dissected, skeletally stained PA skeletons from NF stages 46 to 66+. Ventral views, blue is cartilage, red is bone, scale bars are 5 mm and apply to all panels, except the second one in which the NF 46 skeleton is expanded to be comparable in size with the NF 50 skeleton, the NF 46 skeleton was not dissected because of its small size. NF 46–59 covers tadpole growth, NF 59–66 covers metamorphosis and the NF 66–66+ series shows the separation of the LJ cartilage into two pieces at the end of metamorphosis.