Hypostome (tick)

The hypostome (also called the maxilla, radula, or labium) is a calcified harpoon-like structure near the mouth area of certain parasitic arthropods including ticks, 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.

Barbed hypostome (center) of Ixodes holocyclus flanked by paired palps.