Yanoconodon is an extinct genus of eutriconodont mammal that lived in China during the Early Cretaceous period around 122 million years ago.
Description[]
The genus contains the species Y. allini. The holotype fossil of Yanoconodon was excavated in the Yan Mountains about 300 kilometres from Beijing in the Qiaotou member of the Huajiying Formation (which the original authors considered part of the Yixian Formation) of Hebei Province, China, and is therefore of uncertain age. The Qiaotou Member may correlate with the more well-known Early Cretaceous Yixian Formation, and so probably dates to around 122 Million Years ago.
Yanoconodon was a small mammal, barely 13 centimetres long. It had a sprawling posture, and although previously inferred to be semi-aquatic, direct study of its postcrania indicates that Yanoconodon was likely a terrestrial mammal, and that it has features in common with digging, arboreal, and semiaquatic mammals. Yanocodon had lumbar ribs, a feature not seen in modern mammals. The Yanoconodon holotype is so well preserved that scientists were able to examine tiny bones of the middle ear. These are of particular interest because of their "transitional" state: Yanoconodon has fundamentally modern middle ear bones, but these are still attached to the jaw by an ossified Meckel's cartilage. This is a feature retained from earlier stem mammals, and illustrates the transition from a basal tetrapod jaw and ear.
References[]
- https://www.mindat.org/taxon-4975033.html
- https://www.researchgate.net/figure/New-mammal-Yanoconodon-allini-a-Main-part-of-the-holotype_fig1_253372649
- https://www.researchgate.net/figure/Relationship-of-Yanoconodon-alliniAnalysis-of-all-dental-and-skeletal-characters-of_fig2_6446399
- https://www.science20.com/news_articles/yanoconodon_allini_125_million_year_old_fossil_mesozoic_era_new_mammal_species_0
- https://www.researchgate.net/figure/Comparison-of-mandible-and-middle-ear-of-Yanoconodon_fig2_253372649
- https://www.researchgate.net/publication/317486021_The_postcranial_skeleton_of_Yanoconodon_allini_from_the_Early_Cretaceous_of_Hebei_China_and_its_implications_for_locomotor_adaptation_in_eutriconodontan_mammals
Gallery[]
