Editing Heterotardigrada

{{Short description|Class of tardigrades}}
{{Automatic taxobox
| image = Echiniscus succineus (10.3897-evolsyst.3.33580) Figure 2.jpg
| image_caption     = ''Echiniscus succineus'' under [[Phase-contrast microscopy|PCM]] (left) and [[Scanning electron microscope|SEM]] (right)
| taxon             = Heterotardigrada
| authority         = [[Ernst Marcus (zoologist)|Marcus]], 1927
| subdivision_ranks = Families
| subdivision       = 
'''Order [[Arthrotardigrada]]'''<br/>
&nbsp; [[Archechiniscidae]]<br/>
&nbsp; [[Batillipedidae]]<br/>
&nbsp; [[Coronarctidae]]<br/>
&nbsp; [[Halechiniscidae]]<br/>
&nbsp; [[Neoarctidae]]<br />
&nbsp; [[Neostygarctidae]]<br />
&nbsp; [[Renaudarctidae]]<br/>
&nbsp; [[Stygarctidae]]<br/>
&nbsp; [[Styraconyxidae]]<br/>
&nbsp; [[Tanarctidae]]<br />
'''Order [[Echiniscoidea]]'''<br/>
&nbsp; [[Carphaniidae]]<br/>
&nbsp; [[Echiniscidae]]<br/>
&nbsp; [[Echiniscoididae]]<br/>
&nbsp; [[Oreellidae]]
}}

'''Heterotardigrades''' (class '''Heterotardigrada''') is a [[class (biology)|class]] of the [[tardigrade]]s (water bears) that have cephalic appendages and legs with four separate but similar digits or claws on each. 444 species have been described.<ref name=Zhang2011>{{cite journal| author=Zhang, Z.-Q.| title=Animal biodiversity: An introduction to higher-level classification and taxonomic richness | journal=Zootaxa| volume=3148| year=2011| pages=7–12| doi=10.11646/zootaxa.3148.1.3 | url=http://mapress.com/zootaxa/2011/f/zt03148p012.pdf}}</ref>

== Anatomy ==

The anatomy of the reproductive system is an important defining feature in distinguishing the different groups of tardigrades. Heterotardigrades have gonoducts that open to the outside through a preanal gonopore, rather than opening into the rectum as in the  [[Eutardigrada]].

== Ecology ==
Some [[order (biology)|order]]s of heterotardigrades are marine, others are terrestrial, but as for all tardigrades, all are aquatic in the sense that they must be surrounded by at least a film of moisture in order to be active – though they can survive in a dormant state if the habitat dries out.

== References ==
{{Reflist}}

== External links ==

{{Commons category|Heterotardigrada}}
{{Wikispecies|Heterotardigrada}}

* {{ITIS |id=155167 |taxon=Heterotardigrada}}
* {{ITIS |id=155168 |taxon=Arthrotardigrada}}
* {{ITIS |id=155299 |taxon=Echiniscoidea}}

{{Tardigrades}}

{{Taxonbar|from=Q138557}}
{{Authority control}}

[[Category:Heterotardigrada| ]]
[[Category:Ecdysozoa classes]]
[[Category:Taxa named by Ernst Marcus (zoologist)]]