Ontogenetický vývoj nasální oblasti u Discoglossus pictus (Anura: Discoglossidae)

Using histological techniques and computer-aided three-dimensional reconstructions made from serial histological sections, I studied the ontogenetic development of the ethmoidal endocranium and nasal chemosensory organs in discoglossid frog Discoglossus pictus. The nasal cartilages, including the inferior prenasal cartilage, are de novo adult structures. The only larva-derived structures of the adult nasal capsules are the posterior aspects of the solum nasi and septum nasi. I identify a pattern of development for the suprarostral cartilage that differs from previous findings, and probably represents the ancestral anuran pattern. I also identify patterns of development for the ethmoid plate and postnasal wall that occur during early in ontogenesis. The pattern of timing of chondrification of the anterior nasal cartilages more closely coincides with that of the neobatrachian species than that recorded for the pelobatid frog Spea. The olfactory epithelium in larval D. pictus represents one continuous unit of tissue not divided into two separate portions. However, it forms distinct ventromedial diverticulum embeded into roof of the buccal cavity. This particular arrangement may enhance chemosensory sampling during larval period and this diverticulum might be homologous with the ventral olfactory..