Hypostome

A hypostome (also called the maxilla, radula, labium or Unterkiefer), is a calcified harpoon-like structure near the mouth area of certain parasitic arthropods including ticks and mites (Order Acari), that allows them to anchor themselves firmly in place on a host mammal while sucking blood. This mechanism is normally so strong that removal of a lodged tick requires two actions: One to remove the tick, and one to remove the remaining head section of the tick.