 The Pyrenean desman is long with a rounded scale-covered tail of , and weighs .Pyrenean desmans have a long, sensitive nasal trompe provided with hypertrophic vibrissae and chemo-/mechanosensitive Eimer’s organs helping prey detection, and large webbed feet with fringed hairs to increase the swimming surface, and can close off their nostrils and ears to stop water penetration.The desman's body is covered in dark, brownish fur, with the exception of its tail and nose.