Representatives of the family Gastrodoridae were exclusively known from Jurassic deposits in central Europe. Here, the first Cretaceous species, Gastrodorus cretahispanicus n. sp., is recorded from reefal strata of the Eguino Formation (Albeniz Unit) of Albian-Cenomanian age, in western Navarra (northern Spain). Not only does the occurrence of the new species extend the stratigraphic range of the family upward for approximately 45 million years into the mid-Cretaceous, it also constitutes the first record of gastrodorids from southern Europe. For over a century, the taxonomic position of the genus Gastrodorus has been debated. It is revised here and the family Gastrodoridae is given a full superfamily status within the Anomura. The genus Eogastrodorus is also redefined. Gastrodorids underwent a remarkable size reduction from the Middle to Upper Jurassic, which may be explained by their migration into reef environments.