@CloudLine64: No problem - I actually appreciate questions like this! ^^
Like most of my takes on Pokémon, my Magmar is not specifically inspired by one animal but rather attempts to take the creature as it is and apply some speculative biology and anatomy to it, though it takes some inspiration from actual creatures.
Anatomy-ways, my take on Magmar is largely inspired by archosaurians - that is, the group of diapsids that contains living crocodilians and birds as well as extinct non-avian dinosaurs and pterosaurs. I've given it a slightly more dinosaur-like build as opposed to the sort of odd eggy sort of humanoid construction it has in the official art - though I can picture it shifting from a more dinosaurian stance to a more upright-y stance as it requires.
The muzzle was vaguely inspired by anteaters. I always preferred the original designs of Magmar which showed it having this sort of semi-flexible muzzle which I always figured was supposed to look somewhat like the nozzle of a fire hose - before the animators got lazy and started to draw it like some derpy cartoon duck bill (Duck Magmars are a giant pet peeve of mine, btw). Also, the arm scale patterns were vaguely inspired by pangolins.
I'm pretty sure that's about it for my inspirations when it comes to this specific creature.
Anyway, sadly this design is unlikely to really work out as a shirt - but maybe someday I might do a Magmar design. Who knows? There's a hell of a lot of potential there, for sure. ^^