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Akidolestes in situ
akidolestes rostrum

Akidolestes cifellii (Li and Luo 2006; Yixian Formation, Early Cretraceous. 124 mya; NIGPAS 139381A, B) nests as a basal toothed platypus in the large reptile tree, contra the original interpretation that considered the many similarities convergent. Akidolestes was derived from a sister to Kuehneotherium (see below) with long jaws containing many more teeth than is typical for mammals.

As a monotreme, Akidolestes was an egg-layer, yet providing nourishment for its hatchlings with an early form of milk secreting from ventral glands in its skin.

It probably was a fish and tadpole eater and had a thick, probably waterproof, furry coat.

Teeth Prior to the toothless condition found in Ornithorhynchus, phylogenetic predecessors developed more teeth. Akidolestes is one example. Keuhneotherium is yet another (see below).

 

Akidolestes

 
Kuehneotherium
 

Kermack Dm, Kermack KA, Mussett F 1968. The Welsh pantothere Kuehneotherium praecursoris. Journal of the Linnean Society of London, Zoology. 47 (312): 407–423.

Li G and Luo Z-X. 2006. A Cretaceous symmetrodont therian with some monotreme-like postcranial features. Nature, 439:195–200.

Patterson B and Olson EC 1961. A triconodont mammal from the Triassic of Yunnan. In Vandebroek G (ed.), International Colloquium on the Evolution of Lower and Non Specialized Mammals. Koninklijke Vlaamse Academir voor Wetenschappen, Letteren en Schone Kunsten can Belgie 129-191.

Shaw G 1799. The Naturalist's Miscellany.

wiki/Akidolestes
wiki/Kuehneotherium

 
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