Guys, I'm not crazy. Or at least, not for the reasons I thought I was.
See this? This is the hand of a Potto (Perodicticus potto).
Pottos are small, nocturnal primates native to jungles in west-central Africa. They're related to Lorises, Galagos, and (more distantly) Lemurs. They have Absolute Creature™ energy:
Look at that hand. Look how WEIRD it is. See the index finger? NO YOU DON'T because it ISN'T THERE. These fluffy tree-goblins have almost completely lost their index finger, retaining only a vestigial nub. Why? Specifically for the purpose of having creepy little almost-human-but-fundamentally-wrong-in-an-unsettling-way hands (jk it's something to do with better grasping ability).
See, I knew about the Potto. I knew it existed; I knew that it was a small, slow-moving, nocturnal strepsirrhine with some wonky neck vertebrae that it uses for defence. I ALSO knew about those creepy (I use the term affectionately) hands that have a place to put an index finger but no index finger to put there.
HOWEVER, I knew about these two things SEPARATELY. I never made the connection that those amputee-looking hands belonged to the Potto - I spent YEARS under the assumption that they belonged to a lemur of all things, specifically a Sifaka. How did I come to this conclusion? I have no freaking idea. I've been driving myself CRAZY trying to figure out which species of lemur has a vestigial index finger, when all the photos I could find show lemurs which very obviously have all four fingers. I was beginning to think I'd hallucinated it!
Anyway here's a picture of a bunch of different primate hands for your perusal
