Alternative spellings: Ichthyosauri, Ichthyosauri, Ichthysauria
Parent taxon: Eoichthyosauria according to B. C. Moon 2017
See also Gadow 1898, Hay 1902, Hay 1930, Huene 1954, Jaekel 1910, Jaekel 1911, Ji et al. 2016, Klein et al. 2020, Kuhn 1946, Lomax et al. 2024, Maisch and Matzke 2000, McGowan and Motani 2003, Moon 2019, Motani 1999, Motani et al. 1998, Osborn 1903, Osborn 1903, Osborn 1904, Perrier 1928, Roxo 1937, Sander 2000, Sepkoski 2002, Swinton 1934, Williston 1917, Zittel 1890 and Zverkov 2022
Sister taxon: Grippidia
Subtaxa: Baracromia Cetarthrosaurus Ghuizhouichthyosaurus Grippiidae Guanlingichthyosaurus Hueneosauria Ichthyosauroidea Ichthyosaurus australis Ichthyosaurus polyptychodon Ichthyosaurus strombecki Isfjordosaurus Latipinnatoidea Longipinnatoidea Mixosauria Naanchangasaurus Omphalosauridae Parvinatatoridae Parvipelvia Pessosaurus Proteosauridae Quasianosteosauridae Rachitrema Shastosauroidea Sphaerodontes Stenopterygius grandis Thaisauridae Thunnosauria Utatsusauridae