What is "kosmoceratidae"

Kosmoceratidae is an extinct ammonite family from the Callovian (Middle Jurassic) to Early Cretaceous.

Kosmoceratidae are probably the most polymorphic groups of Jurassic ammonites. These ammonoids have a more or less tabulate venter, with lateral or ventrolateral tubercles. The aptychus is double valved with a concentrically ribbed surface.