In the same vein as your mythological anatomy posts, what about multi-tailed animals(ie 9 tailed fox). The spine would probably split at the sacral vertebrae and have separate sets of coccyx in each tail but would all the splits happen on one vertibra or would one split in to three, each splitting to three, or sequences of doubling vertebrae for even numbers of tails. Would the tails emerge inline or more of an array formation? How would you specify one coccyx from another in different tails?
That’s really difficult to answer because there isn’t any real life mammal case that I know of which I can draw inspiration from. The best I can think of is examples in fish. In some species the double tail trait produces mirror image left and right tails, while others (like the betta) end up with top and bottom tails.
So considering that the entire concept is pure fantasy, you’re equally likely to end up with a left-right pair of tails as you are a top-bottom pair. It’s probably more likely to have a single split at each joint, rather than squeezing in multiple splits per joint, and that way you’re likely to end up with more mobility in the mature animal’s tails. Even numbers of tails are more likely this way, unless there is one ‘primary’ tail which never splits and continued in the midline.
Labeling each tail would then become as irritating as labeling the liver. You would have to label them by their point of origin or simply count from the midline out and label them 1 through 4 for both left and right sides, as we do for toes.
So you might end up with an arrangement that looks like:
Cauda primara (primary tail)
Left Cauda 1, 2, 3 and 4
Right Cauda 1, 2, 3 and 4
or alternatively
Cauda Primara
Left lateral
Left ventral
Left dorsal
Left medial
Right lateral
Right ventral
Right dorsal
Right medial
As ways to describe the multiple tails.