Euharamiyida also known as Eleutherodontida, is clade of early mammals or mammal-like cynodonts from the Middle Jurassic to Early Cretaceous of Eurasia and possibly North America. The group is sometimes considered a sister group to Multituberculata,[1] or part of an earlier divergence within the synapsid line.[2][3] It is disputed whether or not they are related to the Haramiyids from the Late Triassic, such as Haramiyavia.[4] The morphology of their teeth indicates that they were herbivorous or omnivorous. Some members of the group are known to be arboreal, including gliding forms similar to modern flying squirrels or colugos.[1][5]
Evolution
The position of euharamyidans is contested. They are either considered crown group mammals as members of Allotheria, related to multituberculates, or they are considered to stem-group mammals within the Mammaliaformes.[1][3] The position is often dependent on the relationships of euharamiyids to the Late Triassic haramiyids such as Haramiyavia and Thomasia. In some studies, the two groups are recovered as unrelated.[6][4]
^X.-Z. Luo, Q.-J. Meng, D. M. Grossnickle, D. Lui, A. I. Neander, Y.-G. Zhang, and Q. Ji. 2017. New evidence for mammaliaform ear evolution and feeding adaptation in a Jurassic ecosystem. Nature 548:326-329.
^ abMao, Fangyuan; Brewer, Philippa; Hooker, Jerry J.; Meng, Jin (2022). "New allotherian specimens from the Middle Jurassic Woodeaton Quarry (Oxfordshire) and implications for haramiyidan diversity and phylogeny". Journal of Systematic Palaeontology. 20: 1–37. doi:10.1080/14772019.2022.2097021. S2CID251708147.
