Interesting Bug in the latest release.
I grabbed the scorpion venom, feather, and bamboo. Met with Ranger Rick (I know that's not his name) and he asked me to create a tranq. Thinking I had all the materials I attempted to build it, I didn't and the formula failed. I grabbed the dart shortly after but now the scorpion venom, feather, and bamboo are missing from my inventory and no longer available where they were.
Unfortunately I don't have a save from right before I failed to create the tranq with the missing dart.