Twig catfish | Smithsonian’s National Zoo and Conservation Biology Institute https://nationalzoo.si.edu/animals/twig-catfish
Twig catfish, named due to their resemblance to twigs, are found throughout the Amazon, Orinoco and Panara rivers, as well as rivers of the Guyana Shield. They are one of the only fish known that have evolved to eat wood as a primary energy source.
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