The axolotl, a unique amphibian, fascinates with its distinct appearance, including external gills and remarkable regenerative abilities. This aquatic salamander has gained popularity as a pet due to its unusual characteristics. While axolotls in their native habitat exhibit a specific coloration, captive breeding has led to a wide array of colors.
Wild Axolotl Color
Wild axolotls, native to Lake Xochimilco in Mexico, typically display a mottled dark brown or olive-green coloration. This natural hue often includes darker spots, providing effective camouflage within their murky aquatic environment. The wild population of axolotls is now critically endangered, contrasting with the diverse colors seen in captive-bred individuals.
Primary Captive Color Morphs
Selective breeding in captivity has produced several distinct color morphs, each with unique visual characteristics. These primary morphs form the basis of the diverse axolotl colors available today.
Wild Type
The “Wild Type” axolotl in captivity mimics the coloration of its wild counterparts, featuring shades of dark gray, green, or brown, often with speckling and iridescent flecks. These captive-bred wild types maintain the camouflage-like appearance, showing gold speckles and an olive undertone.
Leucistic
Leucistic axolotls are characterized by their pale pink or white bodies, complemented by dark eyes, typically black or dark blue, and bright red gills. While often mistaken for albinos due to their pale appearance, their pigmented eyes distinguish them. Some leucistics may also exhibit black speckling, particularly on their face or spine, which can change over time.
Albino
Albino axolotls lack dark pigment entirely, presenting in two main forms. Golden Albinos have a yellowish or golden body with clear or golden eyes and peachy gills. White Albinos display a pinkish-white body with clear or pink eyes. Both albino types are sensitive to bright light due to the absence of melanin.
Melanoid
Melanoid axolotls appear solid black or dark gray. They possess dark eyes without the characteristic gold ring seen in other morphs, and their gills are also dark, blending with their body color. This morph can range from a very dark green to a completely black appearance.
Specialized Genetic Variations
Beyond the primary color morphs, specialized genetic variations create unique patterns and attributes. These variations often involve the absence or modification of specific pigments or the introduction of new genetic traits.
Axanthic
Axanthic axolotls lack yellow pigment, resulting in a grayish or silvery appearance, typically accompanied by dark eyes. They may appear almost as dark as melanoids due to the absence of yellow and iridescent cells.
Green Fluorescent Protein (GFP)
Green Fluorescent Protein (GFP) integration is a genetic modification, not a natural color, where the axolotl glows green under ultraviolet (UV) or blue light. This trait can be combined with any existing morph, such as a GFP leucistic or GFP wild type. The intensity of the glow can vary, with less pigmented axolotls often glowing brighter.
Chimera or Mosaic
Chimera or Mosaic axolotls are rare individuals that display two distinct color patterns on different halves or sections of their body. This results in an irregular mix of colors and patterns across their body. Their eyes and gills may also exhibit varied coloration, reflecting the mosaicism.
Counting Axolotl Colors
Determining an exact number of axolotl colors is challenging because new variations are continually developed through selective breeding. The vast array of colors is better understood as a collection of morphs or categories, with numerous variations possible within each.
The specific combination of pigment cells—melanophores (black-brown), xanthophores (yellow-red), and iridophores (shiny iridescence)—determines an axolotl’s color. Since genes from parents combine uniquely in each offspring, every new axolotl can be a distinct individual. This ongoing genetic development means there is no fixed number, but rather a dynamic spectrum of colors and combinations that continue to expand. The remarkable diversity available to enthusiasts today is a testament to the extensive efforts in selective breeding.