Eomaia and Monodelphis sort of switch places and wombats are added to the LRT

Today
I added Vombatus (Geoffroy 1803; 98 cm long; extant) and Thylacoleo (Owen 1859; 114 cm long; <2mya;  ) to the large reptile tree (now 783 taxa). Here (subset Fig. 1) they nested together as they do traditionally and share with Macropus protruding dentary incisors that are only incipient in Anebodon.

Revision to the earlier posted basal mammal cladogram. Here two wombats are added. Eomaia and Monodelphis switch places.

Here two wombats are added. Eomaia and Monodelphis switch places.

While rummaging around the marsupials…
I checked data for Monodelphis (Burnett 1830) based on newly found Digimorph.org photos. Previously I had relied on drawings. The differences in data got rid of several autapomorphies and shifted Monodelphis closer to traditional placentals and Eomaia (Ji et al. 2002) closer to Thylacinus, with which it apparently shares a digitigrade manus and pes. You might remember Monodelphis has no pouch. Eomaia was hailed as the basalmost eutherian. That I’ll have to look into further and will report when the dust has settled. I have not updated the online pages yet for these taxa.

Figure 2. Monodelphis skull in three views. Note the supra occipital is narrower than the exoccipitals, like other mammals, not like the data from the figure previously used.

Figure 2. Monodelphis skull in three views. Note the supra occipital is narrower than the exoccipitals, like other mammals, not like the data from the figure previously used.

References
Burnett GT 1830. Illustrations of the Quadrupeda, or Quadrupeds, being the arrangement of the true four-footed Beasts indicated in outline. Quarterly Journal of Science, Literature and Art, July to December, 1829, 336–353.
Ji et al 2002. The earliest known eutherian mammal, Nature 416:816-822.
Pine RH, Flores DA and Bauer K 2013. The second known specimen of Monodelphs unistriata (Wagner) (Mammalia: Didelphimorphia), with redescription of the species and phylogenetic analysis. Zootaxa3640 (3):425-441.

wiki/Monodelphis
wiki/Eomaia

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