order small shrimp like crustaceans common stems presence brood females fact larvae free swimming order head bears pair eyes pairs antennae consists segments bearing branching limbs concealed beneath protective abdomen segments usually small limbs found world shallow deep marine waters benthic important fresh water ecosystems benthic species daily vertical higher parts water column filter feed algae laboratory experimental purposes food source marine organisms sensitive water pollution monitor water quality description head bears pairs antennae pair large eyes head segment segments fused form segments covered attached segments bear filter organic water pairs branching limbs known swimming water feeding unlike true females beneath brood enclosed large flexible flaps extend basal segments form floor chamber animal chamber eggs development direct cases abdomen segments bear absent females fourth longer males specialized function majority species long vary colour pale transparent bright orange brown differ species featuring located abdominal segment help animal orient water clearly seen circular features distinguish shrimp like organisms distribution cosmopolitan distribution found marine freshwater environments deep sea shallow coastal waters lakes rivers underground waters primarily marine fewer percent found freshwater freshwater species total predominantly found zones non marine occur distinct types habitats species isolated basin enormously species glacial subterranean behaviour species benthic living living mid water found close crawling mud sand marine species benthic day leave night swimming purpose live algae solitary form dense form important diet fish general free living species subfamily associated sea crabs taxa described different freshwater habitats caves close relatives inhabit cold deep lakes cycle vertical majority feeding algae common adults young emerge species filter creating feeding current food particles ventral food groove passed filtered second larger prey caught trap composed benthic species especially members subfamily observed feeding small particles collected surfaces bodies legs individual male female external tubular shape males eighth segment pair long female sixth segment attached seventh form brood mating usually takes place night lasts minutes process male releases sperm female eggs usually released hour retained development embryos brood direct young hatching eggs miniature adults size brood generally body length environmental factors density food availability age reach sexual maturity depends water temperature food availability species normally days young released soon numbers usually low short reproductive cycle adults means new brood produced seven days species easy culture large scale laboratory highly tolerate wide range conditions despite low species short reproductive cycle means quickly reproduce vast numbers static flow systems having shown able maintain higher density static system flow systems juvenile continuously separated adult brood stock order reduce mortality shrimp juveniles hours common food cultures enriched highly increase value thought provide ideal food source marine organisms fed cephalopods fish larvae commercial farmed shrimp small size low cost high protein fat content makes good alternative live enriched feeding juveniles especially difficult maintain young small fauna sensitivity water quality makes suitable frequently test toxic substances found sensitive periods belong means near respects appear similar main characteristic separating lack free swimming larvae order extensive currently includes approximately genera containing species traditionally united externally similar group crustaceans broader order classification generally abandoned present previous grouping good morphological support molecular studies group previously included families placed separate order classification
Mysida