Editing Stingray (section)

==Stingray injuries==
{{Main|Stingray injury}}
[[File:Stringray's sting.jpg|thumb|upright=1.5|The stinger of a stingray is known also as the spinal blade. It is located in the mid-area of the tail and can secrete venom. The ruler measures {{Convert|10|cm|abbr=on}}.]]

Stingrays are not usually aggressive and ordinarily attack humans only when provoked, such as when they are accidentally stepped on.<ref name="Slaughter">{{cite journal |last1=Slaughter |first1=Robin J. |last2=Beasley |first2=D. Michael G. |last3=Lambie |first3=Bruce S. |last4=Schep |first4=Leo J. |title=New Zealand's venomous creatures |journal=The New Zealand Medical Journal |date=27 February 2009 |volume=122 |issue=1290 |pages=83–97 |pmid=19319171 }}</ref> Stingrays can have one, two or three blades. Contact with the spinal blade or blades causes local trauma (from the cut itself), pain, swelling, muscle cramps from the venom and, later, may result in infection from bacteria or fungi.<ref>{{cite web|title=Stingray Injury Case Reports|url=http://www.toxinology.com/fusebox.cfm?staticaction=marine_vertebrates%2Fns-stingray_injuries.html|work=Clinical Toxicology Resources|publisher=University of Adelaide|access-date=22 October 2012|archive-date=4 April 2019|archive-url=https://web.archive.org/web/20190404015645/http://www.toxinology.com/fusebox.cfm?staticaction=marine_vertebrates%2Fns-stingray_injuries.html|url-status=live}}</ref> The injury is very painful, but rarely life-threatening unless the stinger pierces a vital area.<ref name="Slaughter"/> The blade is often deeply barbed and usually breaks off in the wound. Surgery may be required to remove the fragments.<ref>{{cite journal | vauthors = Flint DJ, Sugrue WJ | title = Stingray injuries: a lesson in debridement | journal = The New Zealand Medical Journal | volume = 112 | issue = 1086 | pages = 137–8 | date = April 1999 | pmid = 10340692 }}</ref>

Fatal stings are very rare.<ref name="Slaughter"/> The [[death of Steve Irwin]] in 2006 was only the second recorded in Australian waters since 1945.<ref>{{Cite web| url=https://scienceline.org/2006/09/ask-grant-irwin/|author=Hadhazy, Adam T. |work=Scienceline| title=I thought stingrays were harmless, so how did one manage to kill the "Crocodile Hunter?"| date=2006-09-11| access-date=2018-11-18| archive-date=2022-03-29| archive-url=https://web.archive.org/web/20220329163907/https://scienceline.org/2006/09/ask-grant-irwin/| url-status=live}}</ref> The stinger penetrated his [[thoracic wall]] and pierced his heart, causing massive trauma and bleeding.<ref>[http://animal.discovery.com/fansites/crochunter/steve-irwin/stingray/stingray.html Discovery Channel Mourns the Death of Steve Irwin] {{Webarchive|url=https://web.archive.org/web/20130107070254/http://animal.discovery.com/fansites/crochunter/steve-irwin/stingray/stingray.html |date=2013-01-07 }}. animal.discovery.com</ref>

=== Venom ===
[[File:Wikipedia Project Anatomy Of Stingray Tail.svg|thumb|Posterior anatomy of a stingray. (1) Pelvic fins (2) Caudal tubercles (3) Stinger (4) Dorsal fin (5) Claspers (6) Tail]]
The [[venom]] of the stingray has been relatively unstudied due to the mixture of venomous tissue secretions [[Cell (biology)|cells]] and [[mucous membrane]] cell products that occurs upon secretion from the spinal blade. The spine is covered with the epidermal skin layer. During secretion, the venom penetrates the [[epidermis]] and mixes with the mucus to release the venom on its victim. Typically, other venomous organisms create and store their venom in a [[gland]]. The stingray is notable in that it stores its venom within tissue cells. The toxins that have been confirmed to be within the venom are [[cystatin]]s, [[peroxiredoxin]] and [[galectin]].<ref>{{cite journal | vauthors = da Silva NJ, Ferreira KR, Pinto RN, Aird SD | title = A Severe Accident Caused by an Ocellate River Stingray (''Potamotrygon motoro'') in Central Brazil: How Well Do We Really Understand Stingray Venom Chemistry, Envenomation, and Therapeutics? | journal = Toxins | volume = 7 | issue = 6 | pages = 2272–88 | date = June 2015 | pmid = 26094699 | pmc = 4488702 | doi = 10.3390/toxins7062272 | doi-access = free }}</ref> Galectin induces cell death in its victims and cystatins inhibit defense enzymes. In humans, these toxins lead to increased blood flow in the superficial capillaries and cell death.<ref>{{cite journal | vauthors = Dos Santos JC, Grund LZ, Seibert CS, Marques EE, Soares AB, Quesniaux VF, Ryffel B, Lopes-Ferreira M, Lima C | title = Stingray venom activates IL-33 producing cardiomyocytes, but not mast cell, to promote acute neutrophil-mediated injury | journal = Scientific Reports | volume = 7 | issue = 1 | pages = 7912 | date = August 2017 | pmid = 28801624 | pmc = 5554156 | doi = 10.1038/s41598-017-08395-y | bibcode = 2017NatSR...7.7912D }}</ref> Despite the number of cells and toxins that are within the stingray, there is little relative energy required to produce and store the venom.

The venom is produced and stored in the secretory cells of the [[vertebral column]] at the mid-distal region. These secretory cells are housed within the ventrolateral grooves of the spine. The [[Cell (biology)|cells]] of both marine and freshwater stingrays are round and contain a great amount of [[Granule (cell biology)|granule]]-filled cytoplasm.<ref name = "Pedroso_2007">{{cite journal | vauthors = Pedroso CM, Jared C, Charvet-Almeida P, Almeida MP, Garrone Neto D, Lira MS, Haddad V, Barbaro KC, Antoniazzi MM | title = Morphological characterization of the venom secretory epidermal cells in the stinger of marine and freshwater stingrays | journal = Toxicon | volume = 50 | issue = 5 | pages = 688–97 | date = October 2007 | pmid = 17659760 | doi = 10.1016/j.toxicon.2007.06.004 | bibcode = 2007Txcn...50..688P }}</ref> The stinging cells of marine stingrays are located only within these lateral grooves of the stinger.<ref>{{cite journal | vauthors = Enzor LA, Wilborn RE, Bennett WA | date = December 2011 | title=Toxicity and metabolic costs of the Atlantic stingray (Dasyatis sabina) venom delivery system in relation to its role in life history |journal=Journal of Experimental Marine Biology and Ecology|volume=409|issue=1–2|pages=235–239|doi=10.1016/j.jembe.2011.08.026 | bibcode = 2011JEMBE.409..235E }}</ref> The stinging cells of freshwater stingray branch out beyond the lateral grooves to cover a larger surface area along the entire blade. Due to this large area and an increased number of proteins within the cells, the venom of freshwater stingrays has a greater toxicity than that of marine stingrays.<ref name = "Pedroso_2007" />