Desert Tarantula Aphonopelma iodius

This Mojave Desert tarantula has given taxonomists a headache for years—scientists keep combining and separating it from other closely related species, unable to quite agree on what counts as a distinct tarantula. The confusion matters because DNA and field research reveal these desert dwellers are trickier to classify than expected, constantly reshuffling the family tree.

If you're hiking through the Mojave west of the Colorado River, there's a decent chance you'll encounter this species buried in the sandy soil. They're common enough to be a regular part of the ecosystem, yet we're still figuring out exactly who they are.