Why did Christina, O'Brien's pet tarantula completely disappear after the episode "Realm of Fear?" According to the link below, she is never even mentioned again. =( Christina (Memory Alpha link) Not the most fascinating Star Trek question ever, but I have a few tarantulas of my own (hence the interest). I find it really incredible that they have Mexican Red Knee (aka Brachypelma smithi for those tarantula keepers who get upset when only the "common names" are used) tarantulas on an alien planet (sarcasm). Christina happens to be a species of tarantula I don't own, specifically because they seem to love to flick urticating hairs your way.