Chondrichthyes
Also known as cartilaginous fishes, cartilaginous fish, chondrichthyan, chondrichthyans
Chondrichthyes (; ) is a class of jawed fish that contains the cartilaginous fish or chondrichthyans, 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 opercula and swim bladders. Within the infraphylum Gnathostomata, cartilaginous fishes are distinct from all other jawed vertebrates.
AI overview
Chondrichthyes is a class of jawed fish with skeletons made primarily of cartilage rather than bone, which includes sharks, rays, and related species. These aquatic vertebrates are distinguished from other jawed fish by features like their cartilaginous skeletons, paired fins and nostrils, and the absence of gill covers and swim bladders.
AI-generated from the Wikipedia summary — may contain errors.
Species
Parvphylum
- PhylumChordata
Habitatmarine, brackish, freshwater
软骨鱼类是一种古老的鱼类，进化自盾皮鱼。软骨鱼类是現存有頜鱼类中最低等的类群，除了牙齿为硬骨外，骨骼全部由软骨组成，体被盾鳞或无鳞；鳃裂每侧5－7个分别开口于体外，或4个外被一膜质鳃盖；雄性的腹鳍里侧具有鳍脚；尾鳍呈歪尾型；肠具有螺旋瓣；无鳔；具有鰓 裂；软骨鱼类的生殖方式是体内受精，卵生、卵胎生或胎生。 軟骨魚绝大多数在海洋中生活，但它们却起源于淡水生活的祖先。 目录 1 进化 2 分类 3 参见 4 参考文献 进化 软骨鱼和硬骨鱼，一起出现在泥盆纪，它们不断进化，最后取代了盾皮鱼类。现存的2万多种鱼类中，根据其骨骼的性质，可分为软骨鱼和硬骨鱼两大类。 分类 现存的软骨鱼类主要分为板鳃亚纲和全头亚纲（银鲛）两个亚纲。其中板鳃亚纲包括鲨鱼、魟、鳐、锯鳐等。 参见 軟骨 硬骨鱼 参考文献 ^ Botella, H.A.; Donoghue, P.C.J.; Martínez-Pérez, C. Enameloid microstructure in the oldest known chondrichthyan teeth. Acta Zoologica. 2009, 90 (Supplement): 103–108 [26 November 2013]. doi:10.1111/j.1463-6395.2008.00337.x. ^ Chondrichthyes. PalaeoDB. [26 November 2013]. 查 论 编 按亞門與綱分類的現存脊索動物 界: 動物界 亞界: 真后生动物 （未分级）: 两侧对称动物 超門: 後口動物總門＞脊索動物門 尾索動物亞門 海鞘綱、樽海鞘纲、尾海鞘綱、深水海鞘綱（英语：Sorberacea） 頭索動物亞門頭索綱 脊椎動物亞門無頜總綱 盲鰻綱、七鰓鰻綱 有頜下門 軟骨魚 軟骨魚綱 硬骨魚 輻鰭魚、肉鰭魚 四足總綱 兩棲綱 羊膜動物 哺乳綱 蜥形綱 傳統爬蟲類（喙頭蜥目 + 有鱗目 + 龜鱉目 + 鱷目）、鳥綱 物種識別信息 維基數據: Q25371 維基物種: Chondrichthyes ADW: Chondrichthyes EoL: 2774522 EPPO: 1CHONC Fossilworks: 34422 iNaturalist: 196614 IRMNG: 1155 ITIS: 159785 NCBI: 7777 NZOR: 4acd6aba-2825-45a9-8143-ae4486ceeeb7 uBio: 179479 取自“https://zh.wikipedia.org/w/index.php?title=軟骨魚綱&oldid=52994193” 分类：軟骨魚綱 隐藏分类：物种微格式条目
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Article
14 sectionsContents
- Anatomy
- Skeleton
- Appendages
- Body covering
- Respiratory system
- Nervous system
- Immune system
- Reproduction
- Classification
- Evolution
- Taxonomy
- See also
- References
- Further reading
Chondrichthyes (; ) is a class of jawed fish that contains the cartilaginous fish or chondrichthyans, 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 opercula 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 chondrichthyans range in size from the finless sleeper ray to the over whale shark.