So basically, why i asked what animal this bijuu is is because:
1. That isn't revealing anything important if true
2. Animals are different than in og Naruto
3. Pretty sure Ekko didn't just slap tails on random animals and there's some theme or sth like that, basically it's not easy to made it up on spot.
But there's no answer so unless someone has some revelations, i'm good with my vote rn