Editing Skate (fish) (section)

== Description ==
=== General Batoidea characteristics ===
Skates are cartilaginous fishes like other [[Chondrichthyes]], however, skates, like rays and other [[Rajiformes]], have a flat body shape with flat [[pectoral fins]] that extend the length of their body.<ref name=":02">{{cite web|url=https://www.floridamuseum.ufl.edu/fish/discover/rays-skates/anatomy/|title=Ray & Skate Anatomy :: Florida Museum of Natural History|website=www.floridamuseum.ufl.edu|date=5 May 2017|language=en|access-date=2018-03-10}}</ref> This structure creates power for forward propulsion, providing the emergence swimming capabilities that enabled skates to colonize the sea floor.<ref name='nature2023'/>

A large portion of the skate's dorsal body is covered by rough skin made of [[placoid scales]]. Placoid scales have a pointed tip that is oriented caudally and are homologous to teeth. Their mouths are located on the underside of the body, with a jaw suspension common to Batoids known as euhyostyly.<ref name=":8">{{Cite book|last1=Berkovitz|first1=Barry|last2=Shellis|first2=Peter|pages=5–27|doi=10.1016/b978-0-12-802850-6.00002-3|title = The Teeth of Non-Mammalian Vertebrates|year = 2017|isbn = 9780128028506}}</ref> Skate's [[gill slit]]s are located ventrally as well, but dorsal [[Spiracle (vertebrates)|spiracles]] allow the skate to be partially buried in floor sediment and still complete respiratory exchange.<ref name=":5">{{cite journal |author1=Carlos Bustamente |author2=Julio Lamilla |author3=Francisco Concha |author4=David A. Ebert |author5=Michael B. Bennett |author-link2=Julio Lamilla |title=Morphological Characters of the Thickbody Skate Amblyraja frerichsi (Krefft 1968) (Rajiformes: Rajidae), with Notes on Its Biology |journal=[[PLOS One]] |date=29 June 2012 |volume=7 |issue=8 |pages=e39963 |doi=10.1371/journal.pone.0039963 |pmid=22768186 |pmc=3386969 |bibcode=2012PLoSO...739963B |doi-access=free }}</ref> Also located on the dorsal side of the skate are their two eyes which allow for predator awareness.<ref name=":02" /> In addition to their pectoral fins, skates have a first and second [[dorsal fin]], [[Fish fin|caudal fin]] and paired [[pelvic fin]]s. Distinct from their rhomboidal shape is a long fleshy slender tail. While skate anatomy is similar to other Batoidea, features such as their [[Electric organ (biology)|electric organ]] and [[mermaid's purse]] create clear distinctions.
[[File:Mermaidpurse.jpg|thumb|Full view of a skate's mermaid's purse. Roughly 125 mm in length.]]

=== Skate specific characteristics ===
==== Mermaid's purse ====
{{Full article|Mermaid's purse}}
Skates produce their young in an egg case called a mermaid's purse. These egg cases have distinct characteristics that are individualized to each species.<ref name=":03">{{cite journal |last1=Mabragaña |first1=E. |last2=Vazquez |first2=D. M. |last3=Gabbanelli |first3=V. |last4=Sabadin |first4=D. |last5=Barbini |first5=S. A. |last6=Lucifora |first6=L. O. |title=Egg cases of the graytail skate Bathyraja griseocauda and the cuphead skate Bathyraja scaphiops from the south-west Atlantic Ocean |journal=Journal of Fish Biology |date=September 2017 |volume=91 |issue=3 |pages=968–974 |doi=10.1111/jfb.13380 |pmid=28868748 |bibcode=2017JFBio..91..968M |hdl=11336/45691|hdl-access=free}}</ref><ref name="Ebert Davis 2007" /> This makes a great tool for identifying different species of skates. One of these identifiable structures is the keel. The keel is a flexible ridge that runs along the outside of the structure. Another characteristic is the number of embryos in the egg case. Some species contain only one embryo while others can have up to seven. The size of the fibrous shell around the case is another characteristic. Some species have thick layers on the exterior.

==== Electric organ ====
[[File:Skate EO cross section .png|thumb|The fibers of the skate electric organ are embedded in the muscles located lateral to the notochord in the tail.]]

The [[Electric organ (biology)|electric organ]] is a characteristic exclusive to aquatic species. Among the Chondrichthyes, the only groups to possess electric organs are the electric ray and the skates. Unlike many other electrogenic fishes, skates are unique in having paired electric organs which run longitudinally through the tail in the lateral musculature of the notochord.<ref name=":22">{{cite journal |last1=Macesic |first1=Laura J. |last2=Kajiura |first2=Stephen M. |title=Electric organ morphology and function in the lesser electric ray, Narcine brasiliensis |journal=Zoology |date=November 2009 |volume=112 |issue=6 |pages=442–450 |doi=10.1016/j.zool.2009.02.002 |pmid=19651501 |bibcode=2009Zool..112..442M }}</ref> The impulses put out by the electric organs of the skate are considered to be weak, asynchronous, long-lasting signals.<ref name=":4">{{Cite journal|last=Koester|first=David M.|title=Anatomy and motor pathways of the electric organ of skates|journal=The Anatomical Record|volume=273A|issue=1|pages=648–662|doi=10.1002/ar.a.10076|pmid=12808649|year=2003|doi-access=free}}</ref> Although the anatomy of the skate's electric organ is well described, its function is poorly understood. Some research suggests the electric impulses are too weak to be a mechanism used for defense or hunting. It is also too irregular to be useful for electrolocation purposes.<ref name=":4"/> The most reasonable explanation in the literature suggests that the electric organ discharges may be used as a form of communication used for reproduction purposes.<ref name=":4"/>