Larvae of three species of Ambystoma that differ in pigment pattern. These patterns are especially distinctive at the hatching stage seen here, when larvae are especially vulnerable to predators.

Axolotls, Ambystoma mexicanum, do not undergo metamorphosis and instead remain in a permanently aquatic, paedomorphic state.  Shown is a wild-type adult as well as a white mutant adult that completely lacks pigment cells due to an early defect in neural crest development.

This species exhibits an early pigment pattern in aquatic larvae consisting of a light horizontal stripe in the middle of the flank and vertical bars of melanocytes over the dorsal flank. Subsequently, the larvae metamorphose and develop a terrestrial adult pigment pattern of bright spots on a dark background.

This species exhibits horizontal melanophore stripes at early larval stages and a uniform brown pattern as a terrestrial adult.  Experimental analyses reveal evolutionarily derived patterning mechanisms, as compared to other salamander species.

Terrestrial adults of six species of Ambystoma exhibiting a variety of pigment patterns including rings, speckling, longitudinal stripes and irregular spots.