Histology Structure Of Skin And Application Of The Epidermis Microornamentation In Classification Of Toad-headed Agama (Phrynocephalus, Agamidae)

To answer the scale sensory organ is mechanoreceptor or not, and whether it has the function of protecting the skin from mechanical injury and hot radiation, the result of olefin section and ice section reveal that scale sensory organ are cap-like protuberances residing in the scale pits, the surface of which takes on disk structure and is covered with long hairs, it is mechanoreceptor, it may have the function of sense hot radiation. Usually one scale has only one receptor, but we observed that some scales of nose possessed one more receptors, which indicated the important role of nose in sensing outside stimuli.There are two explanations about the evolution of microornamentation. The first is the special microornamentation correlate with the special function. For example, adaptations associated with the shedding cycle, mechanical strength, reduction of friction with the substrate/ adjacent scales, light penetration, dirt shedding, locomotion, pheromone movement, and anti-fouling. The other is the special microornamentation mainly affected by phylogenetic evolution. The surface structure and microstructure of skin and skin sensory organ (SSO) of 11species belonging to Phrynocephalus and two outgroup species Treplus sanguinolenta and Laudakia stolicakana were investigated using the scanning electron microscopy. P. helioscopus in the different habitats have the different microornamentation features. Different Phrynocephalus in the same habitat have the obvious different microorna- mentation features. So, the microornamentation can be used to Classify Phrynocephalus, but it can't be the guide line of classification of Phrynocephalus by itself.