What is an Asian swamp eel and what does it look like?

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Welcome to CoreFacts, where we're always short on time and big on science. I'm Jessica Robertson. Today's question is an interesting one.

What is an Asian swamp eel and what does it look like?

Swamp eels are fish, but they are not closely related to other living eels or snake-like marine and freshwater fishes. Unlike the native American eel, swamp eels do not migrate to the ocean to spawn. The swamp eel family includes more than a dozen species. They are native to Central and South America, Africa and Australia and from India to eastern Asia, including much of China. In Asia, swamp eels are widespread and commonly sold live in markets as food for human consumption.

The swamp eel has a snake-like body with no noticeable scales or fins. The head is relatively short and the teeth are small and not easily seen. The gill opening forms a V shape on the lower throat area. The body and head are dark, sometimes dark olive or brown above, but their lower side is usually lighter, often light orange. Some are brightly colored with yellow, black, and gold spots over a light tan or almost-white background. The skin produces a thick mucous layer making the eels difficult to hold.

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