Pigmentary System of the Adult Alpine Salamander Salamandra atra aurorae (Trevisan, 1982)

Abstract

The pigmentary system of skin from adult specimens of the amphibian urodele Salamandra atra aurorae was investigated by light microscope, electron microscope, and biochemical studies. Yellow (dorsum and head) and black (flank and belly) skin was tested. Three chromatophore types are present in yellow skin: xanthophores, iridophores, and melanophores. Xanthophores are located in the epidermis whereas iridophores and melanophores are found in the dermis. Xanthophores contain types I, II, and III pterinosomes. Some pterinosomes are very electron-dense. Black skin has a single type of chromatophore: the melanophores. Some melanophores are located in the epidermis. In contrast to the dermal melanophores, these present, in addition to typical melanosomes, organelles with different morphology and vesicles having a limiting membrane and containing little amorphous material. Both skin types present some pteridines and flavins, though they are qualitatively and quantitatively more abundant in yellow skin extracts.

The conspicuous postmetamorphic coloration of fire salamanders, but not their toxicity, is affected by larval background albedo

“…However, unlike in most amphibians, these will not form dermal chromatophore units (see Bagnara, Taylor, & Hadley, 1968;Lingon & McCartney, 2016). In salamanders of the genera Salamandra, Ambystoma, and Notophthalmus (Forbes, Zaccaria, & Dent, 1973;Oliphant, 1973;Pederzoli & Trevisan, 1990) xanthophores migrate to the epidermis while melanophores and iridophores remain in the dermis (Pederzoli et al, 2003). After metamorphosis, the yellow areas of the skin contains xanthophores in the epidermis and iridophores in the dermis, that is the skin might lack melanophores, while in black areas, all three chromatophores might be present (Pederzoli et al, 2003).…”

Xanthophore Migration from the Dermis to the Epidermis and Dermal Remodeling During Salamandra salamandra salamandra (L.) Larval Development

“…All three types of chromatophores can be found in the dermis, whereas only melanophores are generally observed in the epidermis (6). Exceptions to this rule presenting xanthophores in the epidermis are adults of Notophtalmus viridescens viridescens (7), Ambystoma macrodactylum (8), Salamandra atra aurorae , Salamandra salamandra gigliolii and Salamandra salamandra salamandra (9, 10). The pigment pattern characterized by epidermal xanthophores and dermal melanophores and iridophores has been denominated the ‘dermo‐epidermal chromatophore unit’ (D‐ECU) by Forbes et al .…”

Cultures of Skin Fragments of Salamandra salamandra salamandra (L.) Larvae

“…Exceptions to this rule are Notuphtdmus viridescens viridescens (Forbes et al, 1973), Ambystoma macrodactylurn (Oliphant, 1973), Salamandra atm a u m , Salamandm. salamandm gigliolii, and Salamandra salamandra salamandra (Pedemoli and Trevisan, 1990, Trevisan et al, 1991Restani, 19961, which have xanthophores in the epidermis. In Salamundra sahmandra salamandra larvae, the xanthophores migrate from the dermis to the epidermis at metamorphosis (Restani,19%).…”