Ok I also think it is time for us to see more of the members collections . So without further ado show us your Sphenacodontidae collection . is an extinct family of small to large, advanced, carnivorous, Late Pennsylvanian to  middle Permian pelycosaurs. Sphenacodontid fossils are so far known only from North America and Europe and have one of the most ironic creature ever to have lived in there ranks, Dimetrodon.  And a claw from  the same location.