Octopuses Used in Research Could Receive Same Protections as Monkeys (nature.com)

>Both octopi and octopodes are acceptable spellings, but octopuses is the more widely used spelling, especially in formal writing and speech.

Source: https://grammarist.com/usage/octopi-octopuses/

I feel like this is an issue whose time has come. Given what we know about octopuses, we are compelled to treat them the same as monkeys or whales