Gastropoda
Most of the gastropods of that era belong to primitive groups. A few of these groups still survive today. By the Carboniferous period many of the shapes seen in living gastropods can be matched in the fossil record. Despite these similarities in appearance, the majority of these older forms are not directly related to living forms. It was during the Mesozoic era that the ancestors of many of the living gastropods evolved. One of the earliest known terrestrial (land-dwelling) gastropods is Maturipupa which is found in the Coal measures of the Carboniferous period in Europe. In the case of the common fossil Bellerophon, from Carboniferous limestones in Europe, it is not known whether it is a gastropod or not.