Leaf Worm (5e Creature)
From D&D Wiki
Tiny beast, unaligned
False Appearance. While the worm remains motionless, it is indistinguishable from a normal leaf.
Tail. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 1 slashing damage plus 3 (1d6) poison damage.
Minute predatory insects that feed chiefly on small flying insects, leaf worms are excellent ambushers that climb trees and pose as ordinary leaves, before striking at unwary prey with their tails that are edged with tiny, but incredibly sharp blades that secrete toxins. They are rarely aggressive toward larger animals, but they are opportunistic, feeding on carcasses when other food is scarce. Whole swarms will home in on the corpse, making it appear as though it were covered in thousands of leaves. They are naturally drawn to trees in the process of becoming treants, often nesting in the treant's boughs when it does awaken.