Axolotls, amphibians native to Mexico, captivate many with their unique appearance, particularly their external gills and “smile.” Their diverse colorations spark curiosity, leading to inquiries about the existence of various hues, including the question of whether truly purple axolotls exist. These aquatic creatures remain in a larval state throughout their lives, a phenomenon known as neoteny, making their coloration a frequent topic of discussion.
The Truth About Purple Axolotls
While a purple axolotl is appealing, naturally occurring axolotls do not exhibit true purple. This misconception arises from artificial alteration, specific lighting, and certain natural morphs. Some axolotls are artificially dyed, a harmful and temporary practice. This involves stripping their protective slime coat with acid before applying dyes, which is inhumane.
Perception of purple axolotls also relates to environmental factors and photography. Lighting, camera filters, or digital manipulation can make certain morphs appear purplish. Some natural morphs, like “lavender” axolotls, have a grayish-purple hue, often with silver undertones. While they can appear purplish, they are not a true purple.
Natural Axolotl Color Morphs
Axolotls display a wide array of natural color variations, or morphs, resulting from genetic differences in their pigment cells. The “Wild Type” axolotl, resembling those found in their native habitat, typically features a dark, mottled brown, green, or olive coloration with gold speckles that provide camouflage. These wild types often have dark eyes with a metallic gold ring around the pupil.
“Leucistic” axolotls are predominantly white or pale pink with dark eyes, which distinguishes them from albinos. Their external gills often appear bright red or pink due to visible blood vessels beneath their translucent skin. “Albino” axolotls, on the other hand, lack melanin, resulting in a white or yellowish body with characteristic red or clear eyes. A common variation, the “Golden Albino,” displays a luminous golden-yellow to light tan color with red or clear eyes and often has reflective flecks. “Melanoid” axolotls are characterized by their dark, uniform coloration, ranging from very dark gray to black, and typically lack the shiny speckles seen in wild types.
Understanding Axolotl Pigmentation
The diverse colors of axolotls are determined by specialized pigment cells called chromatophores, which include melanophores, xanthophores, and iridophores. Melanophores contain eumelanin, a pigment responsible for black and brown coloration. Xanthophores produce yellow and reddish pigments, such as carotenoids and pteridines. Iridophores contain crystallized purines, which create a reflective, iridescent effect.
The specific combination, distribution, and presence or absence of these pigment cells, dictated by the axolotl’s genetic makeup, define its color morph. For instance, albino axolotls lack melanophores, while melanoid axolotls have an increased number of melanophores but lack iridophores. The genetic instructions for these pigment cells limit the natural color palette of axolotls, explaining why certain colors, like a true vibrant purple, are not naturally observed.