Vinegaroons, and the defense mechanism is the reason to keep one: threatened, they aim the whip-like tail and spray a concentrated acetic acid mist, which smells exactly like vinegar and is the source of the common name.
No venom, no fangs worth worrying about, and a heavily built animal that burrows and stays underground for long stretches. M. giganteus out of the American Southwest is the species almost everyone keeps. They molt infrequently and slowly, and they live a long time.
Wild-collected seasonally in Texas, New Mexico and Arizona, so supply vanishes outside the warm months. Captive breeding happens but is slow and does not fill the winter gap. Buy in season.