re: A good question.
So, would that mean that we're all Earthlings as opposed to Americans, Europeans?
I'm kiddying, Steve, but, we have also named the areas of Mars: Arabia Terra, Meridiani.../pick the language and or future inhabitants of those areas.
:)
In a way, I have to agree with you on this one:
"I would say they are earthworms on Mars, after all they came from earth and as long as you don’t breed them with a worm from another planet they would remain earthworms.
I think it would be sad to rename a breed of dog or any animal because it was born on Mars."
I've thought my answer over and I came up with the same answeras you, UNLESS, the animal or plant showed signs of change/evolution to the new environment.
Yes, a good question ahead of its time.