Simpsonodon

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Simpsonodon
Temporal range: Bathonian-Callovian
~165–162  Ma
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Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Therapsida
Clade: Cynodontia
Clade: Mammaliaformes
Order: Docodonta
Genus: Simpsonodon
Kermack et al, 1987
Type species
Simpsonodon oxfordensis
Kermack et al, 1987
Other species
  • S. sibiricus
    (Averianov et al, 2010)

Simpsonodon is an extinct genus of docodontan mammaliaform known from the Middle Jurassic of England, Kyrgyzstan and Russia. The type species S. oxfordensis was described from the Kirtlington Mammal Bed and Watton Cliff in the Forest Marble Formation of England. It was named after George Gaylord Simpson, a pioneering mammalologist and contributor to the Modern Evolutionary Synthesis. [1] A second species S. sibiricus is known from the Itat Formation of Russia, [2] and indeterminate species of the genus are also known from the Balabansai Formation in Kyrgyzstan [3]

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<i>Kermackodon</i>

Kermackodon is an extinct genus of allotherian mammal, known from the Middle Jurassic of England. It combines features of multituberculates with those of euharamyidans. The remains of type species, K. multicuspis were collected from Kirtlington Quarry in Oxford, England, by a team lead from UCL led by Professor Kenneth Kermack after whom the taxon is named, from sediments of the Forest Marble Formation, dating to the Bathonian stage of the Middle Jurassic. The genus and species were named by Percy M. Butler and Jerry Hooker in 2005. The remains comprise a left upper molar (M2), a lower last premolar, initially considered a left but later considered more likely to be right (p4), and an incomplete non-last upper premolar. A second species, K. oxfordensis, from Kirtlington and also sediments of the White Limestone Formation at Woodeaton Quarry was assigned to the genus in 2022, originally placed in the separate genus Eleutherodon. A 2020 study considered it to be more closely related to mutlituberculates than to euharamiyidans, while the 2022 study considered it to be a member of Euharamiyida.

References

  1. KERMACK, K. A.; LEE, A. J.; LEES, PATRICIA M.; MUSSETT, FRANCES (January 1987). "A new docodont from the Forest Marble". Zoological Journal of the Linnean Society. 89 (1): 1–39. doi: 10.1111/j.1096-3642.1987.tb01342.x . ISSN   0024-4082.
  2. Averianov, A. A.; Lopatin, A. V.; Krasnolutskii, S. A.; Ivantsov, S. V. (2010). "New docodontians from the Middle Jurassic of Siberia and reanalysis of docodonta interrelationships" (PDF). Proceedings of the Zoological Institute RAS. 314 (2): 121–148. doi:10.31610/trudyzin/2010.314.2.121. S2CID   35820076.
  3. Martin, Thomas; Averianov, Alexander O. (2010-05-18). "Mammals from the Middle Jurassic Balabansai Formation of the Fergana Depression, Kyrgyzstan". Journal of Vertebrate Paleontology. 30 (3): 855–871. doi:10.1080/02724631003758045. ISSN   0272-4634. S2CID   128716878.