If you're normally supposed to have arms but don't because you lost them at some point, or were just born with them missing, it doesn't count. This trope is for creatures that are naturally armless.

I removed a couple of examples (see edit history), but I'm not so familiar with many of the others, so I'll just leave them for others to check.

Is there a name for the inversion of this trope, where the arms are there but the legs aren't?