Endermite

Endermites are a purple insect-like species native to The End. They sometimes appear when an Enderman teleports, or when an Ender Pearl is used.

Biology
They resemble the silverfish of the Overworld, only they are purple instead of silver.

Uses
Endermites can be made to spawn inside a minecart by the Player Character by throwing enough enderpearls into the minecart. Then once it has appeared, the Player Character will have to name it, or it will disappear again soon. Then it can be used as highly efficient bait to lure Endermen into traps. Don't ask me why anyone would want to do this, all I did was copy this off of the Minecraft wiki.