Rhizodontida

Rhizodontida Temporal range: late Middle Devonian (Givetian) - Pennsylvanian PreꞒ Ꞓ O S D C P T J K Pg N
A fossil of Sauripterus taylori
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Sarcopterygii
Clade:	Tetrapodomorpha
Class:	†Rhizodontida
Order:	†Rhizodontiformes Andrews & Westoll, 1970
Genera
†Archichthys Hancock & Athey, 1870 †Aztecia Johanson & Ahlberg, 2001 †Barameda Long, 1989 †Gooloogongia Johanson & Ahlberg, 1998 †Hongyu? Zhu et al., 2017 †Letognathus Brazeau, 2005 †Propycnotenion Vorobyeva & Obrucheva, 1977 †Pycnoctenion Vorobeva, 1977 †Rhizodus Owen, 1840 †Rossichthys Johanson et al., 2020[1] †Sauripterus Hall, 1843 †Screbinodus Andrews, 1985 †Strepsodus Huxley, 1865 †Thysanolepis? Vorobyeva, 1977[2] †Vorovjevaia? Young et al., 1992[2]

Rhizodontida is an extinct group of predatory tetrapodomorphs^[3] known from many areas of the world from the Givetian through to the Pennsylvanian - the earliest known species is about 377 million years ago (Mya), the latest around 310 Mya. Rhizodonts lived in tropical rivers and freshwater lakes and were the dominant predators of their age. They reached huge sizes - the largest known species, Rhizodus hibberti from Europe and North America, was an estimated 7 m in length, making it the largest freshwater fish known.