Dryosauridae Temporal range: Middle Jurassic – Early Cretaceous, 164–115 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Dysalotosaurus skeletal mount in Berlin
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	†Ornithischia
Clade:	†Ornithopoda
Clade:	†Iguanodontia
Clade:	†Dryomorpha
Superfamily:	†Dryosauroidea Milner & Norman, 1984
Family:	†Dryosauridae Milner & Norman, 1984
Subgroups
†Callovosaurus †Dryosaurus †Dysalotosaurus †Elrhazosaurus †Eousdryosaurus? †Iyuku †Kangnasaurus? †Valdosaurus

Dryosauridae was a family of primitive iguanodonts, first proposed by Milner & Norman in 1984. They are known from Middle Jurassic to Early Cretaceous rocks of Africa, Europe, and North America.^[1][2][3][4]

Classification

List of genera

• Callovosaurus, from the Middle Jurassic of the United Kingdom, is the oldest known dryosaurid.^[3]
• Dryosaurus, from the Upper Jurassic of the United States, is the type genus of Dryosauridae.
• Dysalotosaurus
• Elrhazosaurus, from the Lower Cretaceous of Niger, was considered a nomen dubium by Poole in 2022^[5]
• Eousdryosaurus, from the Upper Jurassic of Portugal, was originally described as a dryosaurid,^[6] but some phylogenetic analyses have recovered it as an elasmarian.^[7]
• Iyuku, from the Lower Cretaceous of South Africa, is only known from very young specimens,
• Kangnasaurus has been recovered by phylogenetic analysis as either a dryosaurid,^[6] elasmarian,^[7] or non-dryomorph iguanodont.^[5]
• Hesperonyx, from the Upper Jurassic of Portugal, is a dryomorph of uncertain placement that may be either a dryosaurid or closer to ankylopollexians.^[8]
• Valdosaurus, from the Lower Cretaceous of the United Kingdom, has been variously recovered as a dryosaurid^[6][7] or a non-dryomorph iguanodont.^[5]

Phylogeny

Until recently, many dryosaurids have been regarded as dubious (Callovosaurus and Kangnasaurus) or as species of the type member, Dryosaurus (Dysalotosaurus, Elrhazosaurus and Valdosaurus). However, more recent studies redescribe these genera as valid.^{[3][4][9][10][11]} The cladogram below follows Paul M. Barrett, Richard J. Butler, Richard J. Twitchett and Stephen Hutt (2011).^[11]