C. oxoniensis the type species in place of the original C. medius. Making C. oxoniensis the type species of Cetiosaurus secured the name Cetiosaurus for the animal with which it has been traditionally associated. Valid Species The complex naming history can be summarised in a list of Cetiosaurus species: Cetiosaurus oxoniensis Phillips, 1871: type species of Cetiosaurus Doubtful species Cetiosaurus hypoolithicus Owen, 1841: nomen nudum Cetiosaurus epioolithicus Owen, 1841: nomen nudum Cetiosaurus brachyurus Owen, 1842: nomen dubium Cetiosaurus longus Owen, 1842: nomen dubium; = Cetiosauriscus longus (Owen, 1842) McIntosh, 1990 Cetiosaurus medius Owen, 1842: nomen dubium Cetiosaurus giganteus Owen vide Huxley, 1870: nomen nudum Cetiosaurus philippsi Sauvage, 1880 Misassigned and reclassified species Cetiosaurus brevis Owen, 1842: non Cetiosaurus, = Cetiosaurus conybeari Melville, 1849; = Pelorosaurus conybearei (Melville, 1849) Mantell, 1850; = Pelorosaurus brevis (Owen, 1842) Huene, 1927 Cetiosaurus glymptonensis Phillips, 1871: non Cetiosaurus; = Cetiosauriscus glymptonensis (Phillips, 1871) McIntosh, 1990, non Cetiosauriscus Cetiosaurus rigauxi Sauvage, 1874: non Cetiosaurus, pliosaurid Cetiosaurus humerocristatus Hulke, 1874: non Cetiosaurus; = Ornithopsis humerocristatus (Hulke, 1874) Lydekker, 1889; = Pelorosaurus humerocristatus (Hulke, 1874) Sauvage, 1897; = Duriatitan humerocristatus (Hulke, 1874) Barrett, Benson & Upchurch, 2010 Cetiosaurus leedsi (Hulke, 1887) Woodward, 1905: nomen dubium; = Ornithopsis leedsii Hulke, 1887 Cetiosaurus greppini (Huene, 1922) Huene, 1932: nomen dubium, = Ornithopsis greppini Huene, 1922 = Amanzia greppini (Huene, 1922) Schwarz et al., 2020 Cetiosaurus rugulosus (Owen, 1845) Steel, 1970: non Cetiosaurus, = Cardiodon Owen, 1841; = Cardiodon rugulosus Owen, 1845 Cetiosaurus mogrebiensis de Lapparent, 1955: non Cetiosaurus Description Cetiosaurus, or specifically the neotype species C. oxoniensis, is known from relatively complete fossils. These include the three skeletons found by Phillips. One of these is a larger animal (catalogued as OUMNH J13605–13613, J13615–16, J13619–J13688 and J13899), which was chosen by Upchurch & Martin as the lectotype of the species; the second consists of limb bones of a smaller individual (OUMNH J13614) and the third skeleton represents the shoulder blade and hindlimb of a juvenile animal (OUMNNH J13617–8, J13780–1). The Rutland specimen, about 40% complete, increases considerably the number of known skeletal elements, especially in the neck. The skull is largely unknown, perhaps with the exception of the brain case represented by specimen OUMNH J13596. A single tooth crown, OUMNH J13597, has provisionally been referred to the species. Cetiosaurus was, as any sauropod, a long-necked quadrupedal animal. In 2010, Gregory S. Paul estimated the body length at and body mass at