What do you call an elephant that doesn't matter?

What do you call an elephant that doesn't matter?
An irrelephant

This is an elephant joke, and also a pun, but it is mostly a pun that happens to have an elephant in it. The pun is centered around the word irrelephant - it sounds quite similar to the word irrelevant. Since  irrelevant means a thing that doesn't matter, and irrelephant must be a portmanteau of elephant and irrelevant, then the word should actually mean an elephant that doesn't matter.

That being said, the joke isn't really all that good.