Amphitheriidae is a family of Mesozoic mammals restricted to the Middle Jurassic of Britain, with indeterminate members also possibly known from the equivalently aged Itat Formation in Siberia and the Anoual Formation of Morocco. They were members of Cladotheria, more derived than members of Dryolestida, and possibly forming a close relationship with Peramuridae. Amphitheriidae is the only family of the order Amphitheriida.
Amphitheriidae is a family of Mesozoic mammals restricted to the Middle Jurassic of Britain, with indeterminate members also possibly known from the equivalently aged Itat Formation in Siberia and the Anoual Formation of Morocco. They were members of Cladotheria, more derived than members of Dryolestida, and possibly forming a close relationship with Peramuridae. Amphitheriidae is the only family of the order Amphitheriida.
== Classification == Cladogram after Panciroli et al. 2018:Cladogram after Magallanes et al, 2024:
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).