Axolotls are some of the most fascinating creatures you can keep as pets. They have feathery gills, wide smiles, and a body shape that looks a lot like a fish. Many people see them swimming in tanks and immediately think, “Oh, that’s a type of fish.” But is that really true? Are axolotls fish, or are they amphibians? The answer might surprise you.
To understand what axolotls really are, we need to look at their biology, life cycle, and unique features. Knowing whether they are fish or amphibians not only helps us understand them better but also allows us to give them the right care in captivity.
Axolotls Are Amphibians, Not Fish
The scientific truth is clear: axolotls are amphibians. They belong to the class Amphibia and are part of the salamander group. What makes them different from other amphibians is that they do not go through a full metamorphosis like frogs or other salamanders. Instead, they remain in their larval stage for their entire lives, keeping their gills and water-based lifestyle.
This condition is called neoteny, which means reaching adulthood while still keeping juvenile features. Because of neoteny, axolotls look and act like underwater creatures forever. But their body structure, genetics, and biology confirm that they are amphibians, not fish.
What Makes a Fish a Fish?
Fish are aquatic animals that live in water for their entire lives. They usually have gills for breathing, scales covering their bodies, and fins for swimming. Most fish also reproduce by laying eggs in the water. Popular aquarium pets like goldfish, guppies, and bettas all share these traits.
When you first see an axolotl, you might notice they have external gills and spend all their time in water. That makes them look very similar to fish. But appearances can be tricky, and axolotls are more than just water-loving creatures.
What Makes an Amphibian an Amphibian?
Amphibians are a special group of animals that include frogs, salamanders, and newts. They usually have a life cycle that starts in the water and later moves to land. Most amphibians are born as larvae with gills, then develop lungs and legs to live partly on land as adults. Amphibians also have smooth skin that can absorb oxygen and water.
Even though axolotls never fully leave the water, they belong to the amphibian family. More specifically, they are a type of salamander. This might sound confusing, so let’s look deeper into why.
Key Differences Between Axolotls and Fish
To make it even clearer, here are some differences that separate axolotls from real fish.
Body covering: Fish usually have scales, while axolotls have soft, smooth skin without scales.
Breathing system: Fish only breathe through gills, but axolotls have both gills and lungs. They can gulp air from the surface if needed.
Skeleton: Axolotls have a bone structure similar to salamanders, not fish. Their limbs and digits resemble those of other amphibians.
Reproduction: While both lay eggs in water, axolotl eggs are more like amphibian eggs, with a jelly-like coating instead of hard shells.
Classification: Fish belong to the class Pisces or Actinopterygii, but axolotls belong to the class Amphibia.
Why People Confuse Axolotls with Fish
It is easy to see why people make the mistake of calling axolotls fish. They swim like fish, they live in water tanks like fish, and they even eat similar foods like bloodworms and brine shrimp. Many pet stores even keep them in the “fish section.” But once you learn about their biology, it becomes clear that they are amphibians with very unique traits.
The Role of Neoteny in Axolotls
Neoteny is the main reason axolotls confuse people. In most amphibians, like frogs, the young stage is very different from the adult stage. Frogs begin life as tadpoles with gills, then grow lungs, legs, and live on land. Axolotls, on the other hand, never complete this transformation. They keep their gills and remain fully aquatic, but still reach sexual maturity and can reproduce. This unusual life cycle makes them different from both fish and most amphibians, but their classification remains amphibian.
Can Axolotls Ever Become Like Land Salamanders?
Interestingly, under special conditions, axolotls can actually transform into land salamanders. This is rare in captivity, but it has been observed when they are exposed to certain hormones or changes in their environment. When this happens, the axolotl absorbs its gills, grows stronger lungs, and starts living on land like a regular salamander. This shows that axolotls truly belong to the amphibian group, since they still have the potential for metamorphosis.
Why It Matters to Know the Difference
Understanding whether axolotls are fish or amphibians is not just about science trivia. It directly affects how you care for them as pets.
Tank setup: Unlike fish, axolotls need cooler water, around 16°C to 20°C (60°F to 68°F). Warmer water can stress them and shorten their lifespan.
Feeding: Axolotls eat meaty foods like worms, pellets, and small aquatic creatures. They do not thrive on regular fish flakes.
Tank mates: Since axolotls are amphibians, not fish, they often get injured if kept with fast or aggressive fish. Their soft skin and delicate gills make them vulnerable.
Lifespan: Axolotls can live up to 10 to 15 years with good care, which is much longer than most small fish.
Knowing their correct classification helps you provide the right environment, diet, and companions for a healthy, long life.
Fun Facts About Axolotls
Axolotls are often called “Mexican walking fish,” even though they are not fish at all. They are native to lakes near Mexico City, such as Lake Xochimilco. They are famous for their regeneration abilities, being able to regrow legs, tails, and even parts of their heart and brain. They are critically endangered in the wild due to pollution and habitat loss, but they are widely bred in captivity for pets, research, and conservation.
Conclusion
So, are axolotls fish or amphibians? The answer is simple: they are amphibians. They may look like fish because they live in water and have gills, but their biology and classification prove otherwise. Axolotls belong to the salamander family and are unique because of their neoteny, which keeps them in a youthful stage forever.
If you own an axolotl or are thinking about getting one, always remember to treat it as an amphibian, not a fish. Provide the right diet, cooler water, and a safe environment. By doing so, you will enjoy many years with one of the most interesting and unusual pets in the world.
FAQs
Are axolotls amphibians or fish?
Many people call axolotls “Mexican walking fish” for their appearance and aquatic lifestyle, but they are truly amphibians. They are part of the salamander family and keep larval traits like feathery external gills all their life due to neoteny.
Their three-chambered heart, four limbs, and other amphibian characteristics make them special. Unlike most salamanders that undergo metamorphosis into a terrestrial adult form, axolotls remain aquatic, giving them a charm that feels like they never grow up.
Is it okay to touch an axolotl?
An axolotl has very sensitive skin that is protected by a thin slime coat, and this can be easily damaged by handling or too much human contact. Even clean hands may carry harmful bacteria, soaps, or lotions that can hurt their delicate body and leave them stressed.
In some specific and truly unavoidable situations, like tank cleaning, you may need to move them. In my own experience, I once had to shift mine using a soft, fine-mesh net and sometimes a small container. If no tool is at hand, you can also use a carefully cupped, wet hand, but this should be rare and only for safety.
Why did my axolotl turn into a salamander?
An axolotl can become a land-dwelling salamander even though it is a neotenic species that usually retains larval traits into adulthood. This rare metamorphosis may happen because of a genetic predisposition or tiger salamander genes.
Strong environment changes or a genetic condition can trigger hormonal changes that cause the transformation, but it often shortens lifespan.
Are axolotls able to go on land?
Axolotls cannot live on land and will die quickly if kept out of water. They retain their feathery external gills and never go through metamorphosis, which keeps them fully aquatic. As neotonic amphibians, they are perfectly adapted to a life in the water for their entire lives, breathing not only with gills but also through their skin.
I once lifted mine for just a moment during cleaning, and it showed me clearly how much safer and calmer it feels when back in the water.
