If you go looking for these creatures; you won't find them; they find you.
If you go to the area where they spawn you'll see a large amount of bonitiod seedlings; what you won't see is the Scourgin under them.
When a bonitiod seedling comes close to you; it dies, and the Scourgin pops out. "The lure dissapears and the Scourgin jumps out at <name>!"