Ultrastructure of the dermal chromatophores in the Fringe-toed lizard, Acanthodactylus orientalis

ABSTRACT Histology and electron microscopic studies of the dorsal skin of the Fringe-toed lizard, Acanthodactylus orientalis Angel, 1936, showed three types of dermal chromatophores: xanthophores, iridophores and melanophores. These pigment cells were observed in vertical combination, with an uppermost layer of xanthophores, an intermediate layer of iridophores and a basal layer of melanophores. The ultrastructure of the melanophore is characterized by oval nucleus and numerous pigment granules, the melanosomes of different stages that remain scattered in the cytoplasm. The chromatophores of this species contain significant information of anatomical similarity with lower as well as higher vertebrates. They can help to better understand the inter relationships between vertebrate pigment cells and their role in skin dysfunctions.