Editing Piranha (section)

==Description==
[[Image:Piranha.jaw.jpg|thumb|Jawbone of ''[[Pygocentrus nattereri]]'']]

===Size===
Depending on the exact species, most piranhas grow to between {{convert|12|and(-)|35|cm|in|abbr=on|0}} long. A few can grow larger, with the largest living species, the [[Red-bellied piranha|red-bellied]], reaching up to {{convert|50|cm|in|abbr=on}}.<ref>{{FishBase genus | genus = Pygocentrus| month = March | year = 2018}}</ref><ref>{{FishBase genus | genus = Serrasalmus| month = March | year = 2018}}</ref> There are claims of [[São Francisco piranha]]s at up to {{convert|60|cm|in|abbr=on}}, but the largest confirmed specimens are considerably smaller.<ref>{{cite web | url=http://www.piranha-info.com/default.php%3Flang%3Den%26id%3Dp_piraya | title=Pygocentrus piraya | publisher=piranha-info.com | access-date=25 March 2018 | archive-date=26 March 2018 | archive-url=https://web.archive.org/web/20180326141735/http://www.piranha-info.com/default.php?lang=en&id=p_piraya | url-status=dead }}</ref> The extinct ''[[Megapiranha]]'' which lived 8–10 million years ago reached about {{convert|71|cm|in|abbr=on}} long,<ref>{{cite journal |last1= Grubich |first1= J.R. |last2= Huskey |first2= S. |last3= Crofts |first3= S. |last4= Orti |first4= G. |last5= Porto |first5= J. |title= Mega-Bites: Extreme jaw forces of living and extinct piranhas (Serrasalmidae) |year= 2012 |journal= Scientific Reports |volume= 2 |page= 1009 |doi= 10.1038/srep01009 |pmid= 23259047 |pmc= 3526859 |bibcode= 2012NatSR...2.1009G }}</ref> and possibly even {{convert|128|cm|in|abbr=on|-1}}.<ref>{{Cite journal|last1=Cione|first1=Alberto Luis|last2=Dahdul|first2=Wasila M.|last3=Lundberg|first3=John G.|last4=Machado-Allison|first4=Antonio|date=2009-06-12|title=Megapiranha paranensis, a new genus and species of Serrasalmidae (Characiformes, Teleostei) from the upper Miocene of Argentina|journal=Journal of Vertebrate Paleontology|volume=29|issue=2|pages=350–358|doi=10.1671/039.029.0221|bibcode=2009JVPal..29..350C |s2cid=86046546|issn=0272-4634}}</ref>

===Morphology===
''Serrasalmus'', ''Pristobrycon'', ''Pygocentrus'', and ''Pygopristis'' are most easily recognized by their unique [[dentition]]. All piranhas have a single row of sharp teeth in both jaws. The teeth are tightly packed and interlocking (via small [[cusp (dentistry)|cusps]]) and are used for rapid puncture and shearing. Individual teeth are typically broadly triangular, pointed, and blade-like (flat in profile). The variation in the number of cusps is minor. In most species, the teeth are tricuspid with a larger middle cusp which makes the individual teeth appear markedly triangular. The exception is ''Pygopristis'', which has pentacuspid teeth and a middle cusp usually only slightly larger than the other cusps.

===Biting abilities===
Piranhas have one of the strongest bites found in bony fishes. Relative to body mass, the black piranha (''[[Redeye piranha|Serrasalmus rhombeus]]'') produces one of the most forceful bites measured in vertebrates. This extremely powerful and dangerous bite is generated by large jaw muscles (adductor mandibulae) that are attached closely to the tip of the jaw, conferring the piranha with a mechanical advantage that favors force production over bite speed. Strong jaws combined with finely serrated teeth make them adept at tearing flesh.<ref>{{Cite journal|title = Mega-Bites: Extreme jaw forces of living and extinct piranhas (Serrasalmidae)|journal = Scientific Reports|date = 2012-12-20|pmc = 3526859|pmid = 23259047|volume = 2|page = 1009|doi = 10.1038/srep01009|first1 = Justin R.|last1 = Grubich|first2 = Steve|last2 = Huskey|first3 = Stephanie|last3 = Crofts|first4 = Guillermo|last4 = Orti|first5 = Jorge|last5 = Porto|bibcode = 2012NatSR...2E1009G}}</ref>