ancestral to all post-early Carboniferous and later ammonoids. Ammonoids again rediversified during the Early Carboniferous. During the Carboniferous ammonoids underwent alternating periods of diversification and decline, and during the late Carboniferous ammonioid diversity became concentrated in a few geographical regions.

During the Permian, the Capitanian mass extinction event severely reduced the diversity of Goniatitida and Prolecanitida,