Fig. 8.

Overview of the diversity of adrostral cartilages among anurans. Ventral view of the jaw region of selected anuran larvae. a Bombina orientalis shows a typical anuran condition of the jaw region consisting of paired infrarostral cartilages, a plate-like suprarostral cartilage and horizontally oriented Meckel’s cartilages. b In Pelobates fuscus (drawn after Nikitin 1986) two so-called adrostral cartilages can be observed lateral to the paired suprarostral cartilages. c Heliophryne orientalis possesses two additional cartilages in the lower jaw. The submeckelian cartilages lie beneath Meckel’s cartilages and the adrostral cartilages are situated lateral to the suprarostral cartilage. In Ly-294,002-treated Xenopus laevis larvae (d) the ectopic cartilages arise lateral to the palatoquadrate and are free from any muscle insertion or origination similar to P. fuscus and H. orientalis