After analysis, Early Cretaceous Bishops is NOT the immediate sister to therian mammals

Flannery et all 2022 concluded,
“Bishopids fam. nov. are the immediate sister taxon to therian mammals.”

The LRT does not confirm this hypothesis of interrelationships.

By contrast, after analysis,
In the large reptile tree (LRT, 2188 taxa), Early Cretaceous Bishops (Fig 1) is a therian mammal close to the Late Cretaceous marsupial Asioryctes (long rostum specimen, Fig 2) and the extant bandicoot (Perameles, Fig 3). So Bishops is not the immediate sister to therian mammals (= marsupials + placentals), contra Flannery et al 2022. It is one of the therian mammals, nested deep inside. Longtime readers of the LRT have known this since 2018.

Unfortunately, Asioryctes is not mentioned in the Flannery et al 2022 text, which deals largely with dental traits. Teeth provide only a few characters in the LRT.

This confirms earlier recoveries by the large reptile tree (LRT, 2189 taxa) based on nesting both Late Jurassic multituberculates and Maiopatagium deep within the placental clade Glires.

“Mesozoic Southern Hemisphere tribosphenic mammals are known from Australia, Madagascar, South America and the Indian subcontinent, and are classified into three families: Bishopidae (fam. nov.), Ausktribosphenidae and Henosferidae. These are stem therians, and considerable morphological evolution occurred within the lineage between the Jurassic and late Early Cretaceous. Important dental modifications include a graduated transition between premolars and molars, development of molar wear facets V and VI, loss of facets for postdentary bones, reduction in the Meckelian groove and development of a true dentary angle. Previous classifications of Southern Hemisphere tribosphenic mammals are ambiguous because information from the upper dentition has been lacking. Upper molars attributed to the late Early Cretaceous (Albian) Southern Hemisphere group Bishopidae fam. nov. are now known to possess a prominent protocone and stylar cusp C. We thus consider bishopids to be the sister group to Theria.”

It’s great to discuss traits, but let’s always rely on the last common ancestor method. Run your analysis, then discuss traits as they apply to related taxa in your cladogram.

According to Wikipedia,
“Tribosphenida is a group (infralegion) of mammals that includes the ancestor of Hypomylos, Aegialodontia and Theria (the last common ancestor of marsupials and placentals plus all of its descendants).”

Not sure why everyone, it seems, is trying to define new clades… unless they are relying on unreliable dental traits. This needs to stop. Use the last common ancestor method based on largely complete skeletons, not genes, not teeth.

Theria still works in the LRT. The other two newer clade names do not.

The key to repairing / improving Flannery et al 2022
is to add Bishops to an analysis that includes a wide gamut of taxa, including the long rostrum specimen of Asioryctes and the bandicoot, Peramelles (Fig 3).

References
Flannery TF et al (4 co-authors) 2022. The Gondwanan Origin of Tribosphenida (Mammalia). Alcheringa: An Australasian Journal of Palaeontology DOI: 10.1080/03115518.2022.2132288
Rich et al 2001. A second tribosphenic mammal from the Mesozoic of Australia. Records of the Queen Victoria Museum 110, 1–9.

Publicity
sciencealert.com/jawbone-discovery-suggests-modern-mammals-originated-in-the-southern-hemisphere

“The researchers suggest the specialized molars of our earliest mammalian ancestors might have been the key to their evolutionary success. But the evolution of early mammals who outlived the dinosaurs has long fascinated scientists and will no doubt continue to attract ongoing scrutiny.”

Let’s remember, dinosaurs are still living as birds. Is this nitpicking?
Or just trying to correct the narrative?

wiki/Tribosphenida
wiki/Theria
wiki/Asioryctes
wiki/Marmosa
wiki/Maelestes
wiki/Bishops