Cyanagraea

Cyanagraea praedator is a species of crab that lives on hydrothermal vents, and the only species in the genus Cyanagraea.^[1][2]

Cyanagraea
A consortium of crabs in an area of hydrothermal activity
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Malacostraca
Order:	Decapoda
Suborder:	Pleocyemata
Infraorder:	Brachyura
Family:	Bythograeidae
Genus:	Cyanagraea de Saint Laurent, 1984
Species:	C. praedator
Binomial name
Cyanagraea praedator de Saint Laurent, 1984

It is found at depths of 2,535–2,630 m (8,317–8,629 ft) on the East Pacific Rise,^[3] where it lives "in the upper part of black smoker chimneys".^[4] Its haemocyanin has a strong affinity for oxygen, and displays a significant Bohr effect, which is unaffected by lactic acid.^[5]

Cyanagraea praedator is "by far the largest" species in the family Bythograeidae, growing to a maximum carapace size of 123.0 mm × 74.8 mm (4.84 in × 2.94 in).^[3]

The leech Bathybdella sawyeri has been observed attached to C. praedator.^[6]