Capybara are categorized as “fish” by the Catholic Church.
“ And though they’re decidedly mammalian, they have been categorized as fish before…by the Catholic church. The Vatican found their webbed feet and affinity for the water as grounds to declare the capybara a fish so that it could be eaten during Lent, a time when meat is forbidden on Fridays but seafood is allowed.”
https://www.fodors.com/news/outdoors/this-dog-sized-rodent-is-your-new-favorite-animal
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