Late Triassic (Norian)

Pant Quarry, fissure fill, near Bridgend, South Glamorgan, Wales

Excellent 1mm tooth

Mammal,

Kuehneotherium is a genus considered to be one of the earliest-known mammals, if not the earliest.  It is found in the same site in Wales as Morganucodon though Kuehneotherium is represented by far fewer specimens.  It’s possible the two belong to separate families.

In a study of the tooth wear of these two genera (see Gill et al., 2014) it was revealed that Kuehneotherium fed on softer-bodied invertebrates than Morganucodon.

Both genera were about the size of modern shrews and likely had a very similar lifestyle.

https://www.nature.com/articles/nature13622