Cyanagraea
Cyanagraea praedator is a species of crab that lives on hydrothermal vents, and the only species in the genus Cyanagraea.
It is found at depths of on the East Pacific Rise, where it lives "in the upper part of black smoker chimneys". Its haemocyanin has a strong affinity for oxygen, and displays a significant Bohr effect, which is unaffected by lactic acid.
Cyanagraea praedator is "by far the largest" species in the family Bythograeidae, growing to a maximum carapace size of.
The leech Bathybdella sawyeri has been observed attached to C. praedator.
