In Polish it's called małpa (monkey). I always thought of this as weird — turns out the Poles were not alone in noticing the resemblance :D

Also “apenstaartje” in Dutch (monkey’s tail)

In Romanian we used to call it literally "monkey's tail", but most people now just use "at" instead.

Zavináč in Slovak (like the fish, sprat, curled into small ball)

German: “Klammeraffe” (literally: “bracket monkey”)

Klammeraffe is a genus of monkey, called spider monkeys [0] in English. “Klammer” here means “clinging”, because these monkeys use their long tail similar to their arms to hold on to branches. “Klammeraffe” has no relation to brackets.

[0] https://en.wikipedia.org/wiki/Spider_monkey