Phronima

{{Short description|Genus of crustaceans}} {{Automatic Taxobox | image = Phronima sedentaria (YPM IZ 075000).jpeg | image2 = Phronima sedentaria 3685226.jpg | image2_caption = Specimens of ''Phronima sedentaria'' | taxon = Phronima | authority = Latreille, 1802 | type_species = ''Cancer sedentarius'' | type_species_authority = Forsskål, 1775 }} thumb|Photnima Sedentaria Offspring '''''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.<ref name="Lowry">{{cite book |author=James K. Lowry |year=2003 |title=Peracarida : Amphipoda, Cumacea, Mysidacea |series=Volume 2, Part 2 of Crustacea: Malacostraca in Zoological catalogue of Australia |publisher=CSIRO Publishing |isbn=978-0-643-06902-2 |chapter=Phronimidae |pages=339–344 |chapter-url=https://books.google.com/books?id=Y5LTA9bAHqYC&pg=PA341}}</ref> ''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.<ref>{{cite web|url=http://www.livescience.com/43076-meet-phronima-the-barrel-riding-parasite-that-inspired-the-movie-alien.html |title=Meet Phronima, The Barrel-Riding Parasite That Inspired The Movie Alien |work=Live Science |author=Katie O'Dwyer |date=February 3, 2014}}</ref> 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.<ref name="Benningfield">{{cite web |url=http://www.scienceandthesea.org/index.php?option=com_content&task=view&id=154&Itemid=10 |title=''Phronima'' |author=Damond Benningfield |date=June 8, 2008 |accessdate=October 11, 2010 |work=Science and the Sea |publisher=University of Texas Marine Science Institute}}</ref> ''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.<ref name="Benningfield"/>

It is sometimes thought to be an inspiration for the fictional xenomorphs.<ref>{{Cite web |last=Leung |first=Tommy |date=2014-01-20 |title=Parasite of the Day: Phronima sp. |url=https://dailyparasite.blogspot.com/2014/01/phronima-sp.html |access-date=2024-07-06 |website=Parasite of the Day}}</ref><ref>{{Cite journal |last=Johnsen |first=Sönke |date=2000 |title=Transparent Animals |url=https://www.jstor.org/stable/26058604 |journal=Scientific American |volume=282 |issue=2 |pages=80–89 |doi=10.1038/scientificamerican0200-80 |jstor=26058604 |pmid=10710790 |bibcode=2000SciAm.282b..80J |issn=0036-8733|url-access=subscription }}</ref>

''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.{{cn|date=December 2024}}

==Classification==

The genus ''Phronima'' contains these 10 species:<ref>{{WoRMS |title=''Phronima'' Latreille, 1802 |db=Amphipoda |id=101804 |access-date=21 September 2024}}</ref> *''Phronima atlantica'' {{small|Guérin-Méneville, 1836}} *''Phronima bowmani'' {{small|Shih, 1991}} *''Phronima bucephala'' {{small|Giles, 1888}} *''Phronima colletti'' {{small|Bovallius, 1887}} *''Phronima curvipes'' {{small|Vosseler, 1901}} *''Phronima dunbari'' {{small|Shih, 1991}} *''Phronima pacifica'' {{small|Streets, 1877}} *''Phronima sedentaria'' {{small|(Forskål, 1775)}} (type species)<ref name="Lowry"/> *''Phronima solitaria'' {{small|Guérin-Méneville, 1844}} *''Phronima stebbingi'' {{small|Vosseler, 1901}}

==References== {{Reflist|30em}} 7. Osborn, K.J., Baldwin Fergus, J. (2020). Hyperiid Amphipod Adaptations to Mid-Ocean Environments. Smithsonian Ocean. National Museum of Natural History.

==External links== *[https://www.google.co.uk/search?q=phronima&source=lnms&tbm=isch&sa=X&ei=oZmaVY_hD4OssAGzm4KgBw&ved=0CAcQ_AUoAQ&biw=1920&bih=1008 Google search for images of Phronima]

Category:Hyperiidea Category:Amphipod genera Category:Taxa named by Pierre André Latreille