On the basis of a fragmentary carapace a new extinct paguroid, Annuntidiogenes massetispinosus n. sp., is described from the upper Meerssen Member (Maastricht Formation, upper Maastrichtian) of the Maastrichtian type area in the southeast Netherlands. The new taxon represents the fifth and stratigraphically youngest member of this Mesozoic genus that shows a remarkably close resemblance to the extant diogenids Aeropaguristes Rahayu and McLaughlin, 2010 (Rahayu DL, McLaughlin PA. 2010. Areopaguristes, a generic replacement name for Stratiotes Thomson, 1899 (Crustacea: Decapoda: Paguroidea: Diogenidae). Zootaxa 2509: 67–68), Paguristes Dana, 1851 (Dana JD. 1851. Conspectus crustaceorum quae in orbis terrarum circumnavigatione, Carolo Wilkes e classe reipublicae foederatae duce, lexit et descripsit. (Preprint from) Proceedings of the Academy of Natural Sciences, Philadelphia 5: 267–272) and Pseudopaguristes McLaughlin, 2002 (McLaughlin PA. 2002. Pseudopaguristes, a new and aberrant genus of hermit crabs (Anomura: Paguridea: Diogenidae). Micronesica 34(2): 185–199). Morphological features of paguroid carapaces, not previously used by neontologists, form the basis for a further systematic refinement of the Paguroidea, with the erection of a new family, the Calcinidae n. fam.