Phronima

Phronima is a genus of small, deep sea hyperiid amphipods of the family Phronimidae. It is found throughout the world's oceans, except in polar regions.^[1] Phronima species live in the pelagic zone of the deep ocean. Their bodies are semitransparent. Although commonly known as parasites, they are more technically correctly called parasitoids.^[2] Instead of constantly feeding on a live host, females attack salps, using their mouths and claws to eat the animal and hollow out its gelatinous shell.^[3] Phronima females then enter the barrel and lay their eggs inside, then propel the barrel through the water as the larvae develop, providing them with fresh food and water.^[3]

Phronima
Specimens of Phronima sedentaria
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Malacostraca
Order:	Amphipoda
Suborder:	Hyperiidea
Family:	Phronimidae
Genus:	Phronima Latreille, 1802
Type species
Cancer sedentarius Forsskål, 1775

Photnima Sedentaria Offspring

It is sometimes thought to be an inspiration for the fictional xenomorphs.^[4][5]

Phronima species possess unique compound eyes adapted to detect blue-green wavelengths of light, which are prominent in the bioluminescent flashes of potential prey and predators. These specialized visual adaptations aid Phronima in navigating the dim mid-ocean environment, where bioluminescence serves as an important ecological signal.^{[citation needed]}

Classification

The genus Phronima contains these 10 species:^[6]

• Phronima atlantica Guérin-Méneville, 1836
• Phronima bowmani Shih, 1991
• Phronima bucephala Giles, 1888
• Phronima colletti Bovallius, 1887
• Phronima curvipes Vosseler, 1901
• Phronima dunbari Shih, 1991
• Phronima pacifica Streets, 1877
• Phronima sedentaria (Forskål, 1775) (type species)^[1]
• Phronima solitaria Guérin-Méneville, 1844
• Phronima stebbingi Vosseler, 1901