The secondary tongue of Salamandra salamandra: histochemical and ultrastructural aspects of the developing lingual epithelium

The development of the lingual epithelium of Salamandra salamandra was inve stigated with emphasis on histochemical and ultrastructural aspects. The te mporal and spatial occurrence and the typical appearance of various cell ty pes, i.e. pavement cells, replacement pavement cells, basal cells, mitochon dria rich cells, goblet cells and glandular cells have been analysed and do cumented in detail from the young larval stage up to the metamorphosed anim al (2 months after metamorphosis). It is shown that anatomical re- and de n ovo-constructions related to the formation of the secretory tongue led to d istinct changes in the cellular equipment of the epithelium of the tongue, including various histochemical properties. Finally, functional aspects of the morphological characteristics are discussed in detail and compared with respective findings in other species.