Casineria kiddi

Casineria is an extinct genus of tetrapod which lived about 340–334 million years ago in the Mississippian epoch of the Carboniferous period. Its generic name, Casineria, is a latinization of Cheese Bay, the site near Edinburgh, Scotland, where the holotype fossil was found. When originally described in 1999, it was identified as a transitional fossil noted for its mix of basal (amphibian-like) and advanced (reptile-like) characteristics, putting it at or very near the origin of the amniotes, the group containing all mammals, birds, modern reptiles, and other descendants of their reptile-like common ancestor. However, the sole known fossil is lacking key elements such as a skull, making exact analysis difficult. As a result, the classification of Casineria has been more controversial in analyses conducted since 1999. Other proposed affinities include a placement among the lepospondyls, seymouriamorphs, "gephyrostegids", or as a synonym of Caerorhachis, another controversial tetrapod which may have been an early temnospondyl.

==Discovery== thumb|left|upright|Location of Cheese Bay in Great Britain In 1992, an amateur fossil collector spotted the remnants of this four-legged creature on the shore of Cheese Bay, Scotland. For the next five years, the fossil languished at the National Museum of Scotland in Edinburgh while researchers focused on other projects. Consisting of a slab and counterslab (compression fossil) of a single partial skeleton, the fossil was cataloged with the specimen designation NMS G.1993.54.1. Around 1997, work began to expose the remainder of the fossil from the surrounding matrix. The work revealed that the animal probably lived in an environment much drier than previously understood. The findings were first reported in the April 8, 1999 edition of Nature.