PaleoDB taxon number: 38755
Alternative spellings: Hydrosauridae, Madrosauridae
Synonyms: Claosauridae Marsh 1890 (no. 52923), Prohadrosauridae Huene 1956 (no. 72196), Protrachodontidae Nopcsa 1915 (no. 96902), Trachodontidae Lydekker 1888 (no. 52931), Trachydontidae Lydekker 1888 (no. 106301), Trachyodontidae Lydekker 1888 (no. 268191)
Full reference: E. D. Cope. 1869. Synopsis of the Extinct Batrachia, Reptilia and Aves of North America. Part I. Transactions of the American Philosophical Society, New Series 14:1-104
Parent taxon: Hadrosauroidea according to P. Cruzado-Caballero and J. E. Powell 2017
Sister taxa: Arstanosaurus akkurganensis, Bactrosaurus, Batyrosaurus, Cedrorestes, Claosaurus, Datonglong, Eolambia, Equijubus, Fukuisaurus, Gilmoreosaurus, Gobihadros, Gongpoquansaurus, Huehuecanauhtlus, Iguanodon hillii, Jeyawati, Jintasaurus, Koshisaurus, Levnesovia, Nanningosaurus, Nanyangosaurus, Ovaloolithidae, Penelopognathus, Plesiohadros, Probactrosaurus, Protohadros, Saurolophidae, Shuangmiaosaurus, Sirindhorna, Spheroolithidae, Tanius, Telmatosaurus, Tethyshadros, Trachodon cantabrigiensis, Xuwulong, Yunganglong, Zhanghenglong, Zuoyunlong
Subtaxa: Arstanosaurus, Cionodon, Claorhynchus, Diclonius, Edmontosaurinae, Eotrachodon, Euhadrosauria, Gryposaurinae, Hadrosaurinae, Hadrosaurus breviceps, Hadrosaurus cavatus, Hadrosaurus minor, Huaxiaosaurus, Hypsibema, Lambeosaurinae, Lapampasaurus, Maiasaurinae, Microhadrosaurus, Nectosaurus, Neosaurus missouriensis, Orthomerus, Parrosaurus, Prohadrosaurinae, Protrachodontinae, Pteropelyx, Saurolophinae, Saurolophus krystofovici, Thespesius, Trachodon, Trachodontinae, Tridigitichnus, Troodon isfarensis, Tyrannosauropus, Willinakaqe
Type: Hadrosaurus
Ecology: ground dwelling herbivore