Anebodon: another symmetrodont or marsupial mole sister?

Updated March 09, 2018 when I realized I had not updated the nesting of this taxon with the golden mole, Notoryctes.

Bi et al. 2016
reported on “Anebodon luoi (STM 38-4, Tianyu Museum of Nature, Shandong Province, China, Fig. 1) a new genus and species of zhangheotheriid symmetrodont mammal from the Lujiatun site of the Lower Cretaceous Yixian Formation, China. The fossil is represented by an associated partial skull and dentaries with a nearly complete dentition.”

Figure 1. Anebodon luoi subjected to DGS tracing and phylogenetic analysis nests with Macropus, the extant kangaroo, not with Zhangheotherium. The kangaroo kink is just starting here with a concave/convex maxilla. The canines are present, but tiny. The anterior dentary teeth extend anteriorly, the first step toward the kangaroo's 'tusks'.

Figure 1. Anebodon luoi subjected to DGS tracing and phylogenetic analysis nests with Macropus, the extant kangaroo, not with Zhangheotherium. The kangaroo kink is just starting here with a concave/convex maxilla. The canines are present, but tiny. The anterior dentary teeth extend anteriorly, the first step toward the kangaroo’s ‘tusks’.

Bi et al. noted
Anebodon lacked the high molar count typical of derived symmetrodonts. Their diagnosis focused on dental differences compared to Maotherium and Kiyatherium.

By contrast
the large reptile tree (LRT) nested Early Cretaceous Anebodon with the the golden mole Notoryctes (Fig. 1). A septomaxilla was identified in Anebodon.

 

The clade
Symmetrodonta is considered paraphyletic at Wikipedia. The clade is based on teeth characterized by the triangular aspect of the molars when viewed from above and the absence of a well-developed talonid. Perhaps such teeth were common to basal placentals.

References
Bi S-D, heng X-T, Meng J, Wang X-L, Robinson N and Davis B 2016. A new symmetrodont mammal (Trechnotheria: Zhangheotheriidae) from the Early Cretaceous of China and trechnotherian character evolution. Nature Scientific Reports 6:26668 DOI: 10.1038/srep26668

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