the plant called tiger's tail, but it looks like ponytail.

This is a plant of the primula family called Lysimachia clethroides and common name in English is gooseneck loosestrife.
In Japan, this is called Oka-torano-o which means land tiger's tail if it is translated literally.
It is said that the name "Oka-torano-o" originated from the shape looking like tiger's tail. But I do not agree to this opinion, because, it does not look like the tail of the tiger at all. If anything, it looks like the tail of pony. Why don't we just call it ponytail?