Editing Copepod (section)

{{Short description|Subclass of crustaceans}}
{{Automatic taxobox
| name = Copepod
| fossil_range = {{fossil range|303|0|[[Pennsylvanian (geology)|Pennsylvanian]] – [[Holocene|recent]]|earliest=Cambrian}}
Likely early [[Paleozoic]] origin
| image = Веслоногие ракообразные разных видов.jpg
| taxon = Copepoda
| authority = [[Henri Milne-Edwards|H. Milne-Edwards]], 1840
| subdivision_ranks = Orders
| subdivision = 
*[[Calanoida]]
*[[Canuelloida]]
*[[Cyclopoida]]
*[[Gelyelloida]]
*[[Harpacticoida]]
*[[Misophrioida]]
*[[Monstrilloida]]
*[[Mormonilloida]]
*[[Platycopioida]]
*[[Siphonostomatoida]]
}}

'''Copepods''' ({{IPAc-en|ˈ|k|oʊ|p|@|p|ɒ|d}}; meaning 'oar-feet') are a group of small [[crustacean]]s found in nearly every [[freshwater]] and [[saltwater]] [[habitat (ecology)|habitat]]. Some species are [[plankton]]ic (living in the water column), some are [[benthos|benthic]] (living on the sediments), several species have [[Parasitism|parasitic phases]], and some continental species may live in limnoterrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests, bogs, springs, ephemeral ponds, puddles, damp moss, or water-filled recesses of plants ([[phytotelmata]]) such as [[bromeliad]]s and [[pitcher plant]]s. Many live underground in marine and freshwater caves, [[sinkhole]]s, or stream beds. Copepods are sometimes used as [[Ecological indicator|biodiversity indicator]]s.

As with other crustaceans, copepods have a [[larva]]l form. For copepods, the egg hatches into a [[Crustacean larvae#Nauplius|nauplius]] form, with a head and a tail but no true thorax or abdomen. The larva molts several times until it resembles the adult and then, after more molts, achieves adult development. The nauplius form is so different from the adult form that it was once thought to be a separate species. The metamorphosis had, until 1832, led to copepods being misidentified as [[zoophyte]]s or [[insect]]s (albeit aquatic ones), or, for parasitic copepods, 'fish [[lice]]'.<ref>{{cite book|last = Damkaer| first = David| title = The Copepod's Cabinet: A Biographical and Bibliographical History| publisher = American Philosophical Society| date = 2002| url = https://archive.org/details/bub_gb_TgUNAAAAIAAJ/page/n135/mode/2up?q=vermes| isbn =9780871692405}}</ref>