gnathostome chondrichthyan http://id.loc.gov/authorities/subjects/sh85024672 http://purl.bioontology.org/ontology/SNOMEDCT/107298006 http://purl.obolibrary.org/obo/NCBITaxon_7777 https://en.wikipedia.org/wiki/Chondrichthyes https://species.wikimedia.org/wiki/Chondrichthyes https://www.wikidata.org/wiki/Q25371 QL638.6-QL638.95 A class that contains the cartilaginous fishes: they are jawed vertebrates with paired fins, paired nares, scales, a heart with its chambers in series, and skeletons made of cartilage rather than bone. The class is divided into two subclasses: Elasmobranchii (sharks, rays, skates, and sawfish) and Holocephali (chimaeras, sometimes called ghost sharks, which are sometimes separated into their own class). Chondrichthyes chondrichthyans