Strangleweed

Strangleweed is a long, clinging vine usually found growing in caves. The vines and leaves are a shiny black; the leaves are sharp as razors and the short, fine spines that cover the vines can catch in the skin of those who brush against it, causing a nasty rash.
Strangleweed is carnivorous. Although it is non-sentient, it can sense when "prey" comes near, entangling its victims in its vines, cutting and strangling them.