Gigantocypris
Encyclopedia
Gigantocypris is a genus of ostracod
crustacean
in family Cypridinidae
, and probably the most famous ostracod in the world. Its members are exceptionally large for ostracods, measuring up to 25 millimetre (0.984251968503937 in) across. The animals are orange–red in life, but live at depths of
900–1300 m (2,952.8–4,265.1 ft), where there is no natural sunlight. Despite this, they are equipped with a pair of large eyes which, rather than using lenses
to focus light onto a retina
, use parabolic mirrors a few millimetres across. It is thought that Gigantocypris uses these eyes to find sources of bioluminescence
for it to predate upon, and it feeds upon copepod
s and small fish.
Ostracod
Ostracoda is a class of the Crustacea, sometimes known as the seed shrimp because of their appearance. Some 65,000 species have been identified, grouped into several orders....
crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
in family Cypridinidae
Cypridinidae
Cypridinidae is a family of ostracods, containing the following genera:*Amphisiphonostra Poulsen, 1962*Azygocypridina Sylvester-Bradley, 1950*Bathyvargula Kornicker, 1968*Codonocera Brady, 1902*Cypridina Milne-Edwards, 1840...
, and probably the most famous ostracod in the world. Its members are exceptionally large for ostracods, measuring up to 25 millimetre (0.984251968503937 in) across. The animals are orange–red in life, but live at depths of
Bathyal zone
The bathyal zone or bathypelagic – from Greek βαθύς , deep – is that part of the pelagic zone that extends from a depth of 1000 to 4000 metres below the ocean surface. It lies between the mesopelagic above, and the abyssopelagic below. The average temperature hovers at about 39°F...
900–1300 m (2,952.8–4,265.1 ft), where there is no natural sunlight. Despite this, they are equipped with a pair of large eyes which, rather than using lenses
Lens (optics)
A lens is an optical device with perfect or approximate axial symmetry which transmits and refracts light, converging or diverging the beam. A simple lens consists of a single optical element...
to focus light onto a retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
, use parabolic mirrors a few millimetres across. It is thought that Gigantocypris uses these eyes to find sources of bioluminescence
Bioluminescence
Bioluminescence is the production and emission of light by a living organism. Its name is a hybrid word, originating from the Greek bios for "living" and the Latin lumen "light". Bioluminescence is a naturally occurring form of chemiluminescence where energy is released by a chemical reaction in...
for it to predate upon, and it feeds upon copepod
Copepod
Copepods are a group of small crustaceans found in the sea and nearly every freshwater habitat. Some species are planktonic , some are benthic , and some continental species may live in limno-terrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests,...
s and small fish.
Species
The genus contains six species:- Gigantocypris agassizii G. W. Müller, 1895
- Gigantocypris australis Poulsen, 1962
- Gigantocypris danae Poulsen, 1962
- Gigantocypris dracontovalis Cannon, 1940
- Gigantocypris muelleri Skogsberg, 1920
- Gigantocypris pellucida G. W. Müller, 1895