Dryolestidae is an extinct family of Mesozoic mammals, known from the Middle Jurassic to the Early Cretaceous of the North Hemisphere.
[5] They are generally classified in Cladotheria, meaning that they are considered to be more closely related to marsupials and placentals than to monotremes.
They are placed as part of the broader Dryolestida, which also includes the (possibly paraphyletic) Paurodontidae, and also sometimes the South American-Antarctic Meridiolestida, which are often considered unrelated cladotherians.
[6] Dryolestidae taxon is not based on a phylogenetic definition, but instead on the possession of unequal roots for the molars of the lower jaw.
Additionally, the clade is distinguished by hypsodonty in lower molars, and uneven labio-lingual height for the alveolar borders of the dentary.