Cartilaginous fishes Early | |
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Example of cartilaginous fishes: Elasmobranchii at the top of the image and Holocephali at the bottom of the image. | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Subphylum: | Vertebrata |
Infraphylum: | Gnathostomata |
Clade: | Eugnathostomata |
Class: | Chondrichthyes Huxley, 1880 |
Living subclasses and orders | |
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Chondrichthyes (/kɒnˈdrɪkθi.iːz/; from Ancient Greek χόνδρος (khóndros) 'cartilage', and ἰχθύς (ikhthús) 'fish') is a class of jawed fish that contains the cartilaginous fish or chondrichthyians, which all have skeletons primarily composed of cartilage. They can be contrasted with the Osteichthyes or bony fish, which have skeletons primarily composed of bone tissue. Chondrichthyes are aquatic vertebrates with paired fins, paired nares, placoid scales, conus arteriosus in the heart, and a lack of opecula and swim bladders. Within the infraphylum Gnathostomata, cartilaginous fishes are distinct from all other jawed vertebrates.
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). Extant Chondrichthyes range in size from the 10 cm (3.9 in) finless sleeper ray to the over 10 m (33 ft) whale shark.