Amphitheriidae

Amphitheriidae Temporal range: Middle Jurassic, 174.7–161.5  Ma PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Clade:	Prototribosphenida
Order:	† Amphitheriida Prothero, 1981
Family:	† Amphitheriidae Owen, 1846
Genera
† Amphitherium † Palaeoxonodon

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. ^[1] Amphitheriidae is the only family of the order Amphitheriida.

Classification

 Cladogram after Panciroli et al. 2018: ^[1]

Cladotheria	Dryolestida Vincelestes Nanolestes Arguimus Peramus Amphitheriidae Kielantherium Aegialodon Theria (modern placentals, marsupials, and relatives)

Cladogram after Magallanes et al, 2024: ^[2]

Cladotheria	Dryolestida Paurodon Drescheratherium Foxraptor Meridiolestida Zatheria Amphitheriidae Peramus Vincelestes Kielantherium Pappotherium Eutheria (placentals and relatives) Metatheria (marsupials and relatives)

References

1. Panciroli E; Roger B.J. Benson; Richard J. Butler (2018). "New partial dentaries of amphitheriid mammalian Palaeoxonodon ooliticus from Scotland, and posterior dentary morphology in early cladotherians". Acta Palaeontologica Polonica. 63 (2). doi: 10.4202/app.00434.2017 .
2. Magallanes, Isaac; Beard, K. Christopher; Martin, Thomas; Luo, Zhe-Xi (2023-09-03). "A new dryolestid fossil from the Late Jurassic illuminates molar root structure of dryolestids" . Journal of Vertebrate Paleontology. 43 (5). doi:10.1080/02724634.2024.2322740. ISSN   0272-4634.

Further reading

• Zofia Kielan-Jaworowska, Richard L. Cifelli, and Zhe-Xi Luo, Mammals from the Age of Dinosaurs: Origins, Evolution, and Structure (New York: Columbia University Press, 2004), 14,395.
• Close RA., Davis BM., Walsh S., Wolniewicz AS., Friedman M. and Benson RB. 2016. A lower jaw of Palaeoxonodon from the Middle Jurassic of the Isle of Skye, Scotland, sheds new light on the diversity of British stem therians. Palaeontology, 59, 155-169