Three-Toed Amphiuma

Amphiuma tridactylum

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Photo of a three-toed amphiuma in an aquarium.
The three-toed amphiuma is an eel-like, completely aquatic salamander that can grow to be two feet long.
Jim Rathert
Species of Conservation Concern
Family

Amphiumidae (amphiumas) in the order Caudata (salamanders)

Description

A completely aquatic salamander shaped like a long cylinder with a somewhat pointed head; it has tiny gray eyes and very small fore- and hind limbs. Each limb has three very small toes. The dorsal color is dark brown or black; the belly is lighter brown or gray. Adults do not have gills, but a gill slit is present on each side of the head. Amphiumas have lungs and must breathe air at the surface of the water. Note that amphiumas often are missing toes or entire limbs. Amphiumas are alert, fast, and slippery and may bite viciously if captured.

Similar species: The western lesser siren (Siren intermedia nettingi) has feathery external gills and lacks hind limbs; in Missouri, its range extends farther north and east than the amphiuma’s. Both of these salamanders can be distinguished from eels and lampreys (which are fish) by their limbs with fingers, tiny eyes, and lack of fins and scales.

Size

Length: 18–30 inches.

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Photo of a three-toed amphiuma showing legs and toes.
Three-Toed Amphiuma
The three-toed amphiuma has four very small legs, each with three very small toes.

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Photo of a three-toed amphiuma showing side of head.
Three-Toed Amphiuma
Adult amphiumas do not have gills. They have lungs and must breathe air at the surface of the water.

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Photo of a three-toed amphiuma showing head.
Three-Toed Amphiuma
If you are fishing and catch an amphiuma, or any other amphibian, cut the line and release it unharmed.

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Photo of a three-toed amphiuma showing nose and jaw.
Three-Toed Amphiuma
Only a small fraction of Missouri’s original cypress swamps — the amphiuma’s habitat — remain.

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Photo of a three-toed amphiuma.
Three-Toed Amphiuma
The three-toed amphiuma lives in the still waters of ditches, sloughs, and swamps. It forages at night.
Habitat and conservation

This salamander lives in still water, such as in ditches, sloughs, and swamps. In Missouri, cypress swamps are preferred. Days are spent buried in silt or hiding under submerged roots, debris, or aquatic plants. Periodically they must come to the surface for air. They forage at night.

Foods

Amphiumas venture forth at night in search of small fish, crayfish, tadpoles, snails, aquatic insects, earthworms, and other aquatic animals.

image of Three-Toed Amphiuma Distribution Map
Distribution in Missouri

The Mississippi Lowlands of southeastern Missouri.

Status

A Species of Conservation Concern in Missouri. The cypress swamps of southeastern Missouri are important to the survival of this interesting amphibian and should be protected. Only a small fraction of Missouri’s original cypress swamps remain. This species is sometimes called “congo eel” and “blue eel,” but it is not a true eel, since eels are fish, and amphiumas are amphibians.

Life cycle

In Missouri, breeding is believed to occur in late summer and early autumn. A female lays an average of 200 eggs on land, usually under a rotten log near water, and the female stays with the eggs until they hatch. Once water from autumn rains covers the eggs, they complete development and hatch. The larvae are gilled but take air from the surface, so they apparently have well-developed lungs upon hatching. The gills are resorbed within about 10 days after hatching.

Human connections

If you are fishing and catch an amphiuma, or any other amphibian, cut the line and release it unharmed. Most amphibian populations are declining, none are venomous, and none threaten our fisheries. They are an integral part of our aquatic fauna.

Ecosystem connections

The western mudsnake of southwestern Missouri specializes in eating our two eel-like amphibians (the amphiuma and the lesser siren). The slippery amphibian thrashes wildly, but the snake pokes its prey with its pointy tail tip. This makes the amphibian uncurl and easier to swallow.