The axolotl, a unique amphibian that retains its aquatic, larval form (neoteny), is often the subject of curiosity regarding its anatomy. Axolotls do have teeth, but their dental structure is profoundly different from the specialized, chewing teeth found in mammals. These small, barely visible structures are an adaptation to their aquatic existence and specialized feeding habits.
The Nature of Axolotl Teeth
Axolotl teeth are minute, conical, and sharp, but they are not designed for tearing or grinding (mastication). They are rudimentary structures evolved primarily for gripping and holding slippery prey. The dentition is composed of several tooth fields arranged in both outer and inner dental arcades. The outer arcade includes small teeth on the premaxilla and dentary bones, while the inner arcade features multiple rows of teeth on the vomerine, palatine, and coronoid bones.
The teeth are constantly replaced throughout the animal’s life, a process known as polydonty, which is typical for many non-mammalian vertebrates. This continuous regeneration ensures a fresh supply of gripping surfaces, which is important since the axolotl swallows its food whole. The vomerine teeth, located on the roof of the mouth, are especially important for securing the meal once it is captured.
How Axolotls Use Their Mouths to Eat
The axolotl’s method of eating relies entirely on suction, often described as vacuum feeding. When the salamander detects prey, it rapidly opens its wide mouth, creating negative pressure that pulls water and the food item directly into the buccal cavity. This action is quick, sucking the prey in whole, often accompanied by surrounding water and substrate.
The tiny, sharp teeth act like a biological ratchet during this vacuum event, helping prevent the captured meal from escaping before it can be swallowed. The axolotl also has gill rakers that interlock to close the gill slits, ensuring water is expelled while the food remains inside the mouth. The primary function of the teeth is to secure the catch, not to break it down.
Diet and Feeding Habits
Due to their suction feeding method and lack of chewing ability, the axolotl’s wild diet consists primarily of small, soft-bodied aquatic organisms. This includes worms, small fish, insect larvae, and crustaceans, which can be swallowed without extensive processing. Their natural habitat in the freshwater lakes and canals near Mexico City historically provided a plentiful supply of this prey.
In captivity, the diet mimics this requirement for high-protein, soft food. Earthworms, specifically nightcrawlers, are highly regarded as a staple due to their complete nutritional profile and texture. Commercial food pellets formulated for carnivorous aquatic animals are also used. Food items must always be smaller than the width of the axolotl’s head to prevent choking, reinforcing how their specialized feeding mechanism constrains their dietary choices.