Editing Mysida (section)

{{Short description|Small, shrimp-like crustacean}}
{{good article}}
{{Automatic taxobox
| name = Mysida 
| image = Hemimysis anomala GLERL 4.jpg
| image_caption = ''[[Hemimysis anomala]]'' ([[Mysidae]])
| taxon = Mysida
| authority = [[Johan Erik Vesti Boas|Boas]], 1883<ref name=WoRMS>{{cite WoRMS |author=Mees, J. |year=2013 |title=Mysida |id=149668 |access-date=2014-01-30 }}</ref> 
| subdivision_ranks =  [[Family (biology)|Families]]
| subdivision =
*[[Mysidae]]
*[[Petalophthalmidae]]
}}

'''Mysida''' is an [[order (biology)|order]] of small, [[shrimp]]-like [[crustacean]]s in the [[malacostraca]]n [[superorder]] [[Peracarida]]. Their [[common name]] '''opossum shrimps''' stems from the presence of a [[Brood pouch (Peracarida)|brood pouch]] or "marsupium" in females. The fact that the [[Crustacean larvae|larvae]] are reared in this pouch and are not [[Motility|free-swimming]] characterises the order. The mysid's head bears a pair of stalked eyes and two pairs of antennae. The thorax consists of eight segments each bearing branching limbs, the whole concealed beneath a protective [[carapace]] and the abdomen has six segments and usually further small limbs.

Mysids are found throughout the world in both shallow and deep marine waters where they can be [[Benthos|benthic]] or [[pelagic]], but they are also important in some [[fresh water]] and [[brackish water|brackish]] [[ecosystem]]s. Many benthic species make [[Diel vertical migration|daily vertical migrations]] into higher parts of the [[water column]]. Mysids are [[filter feeder]]s, [[omnivore]]s that feed on [[algae]], [[detritus]] and [[zooplankton]]. Some mysids are cultured in laboratories for experimental purposes and are used as a food source for other cultured marine organisms. They are sensitive to water [[Pollutant|pollution]], so are sometimes used as [[bioindicator]]s to monitor [[water quality]].