The 25 Recent species and subspecies of the Xenophoridae are reviewed. Three sub genera are recognized within the only genus, Xenophora: Stellaria (with 5 species and 1 subspecies), Onustus (with 4 species), and Xenophora s.s. (with 13 species and 2 subspecies). A brief outline of the fossil history of the group and a general account of the anatomy and habits are given. A new species (X. granulosa sp. nov.) from the central Indo-Pacific and three new subspecies are described, one from the Hawaiian Islands (X. peroniana kondoi subsp. nov.), one from the Gulf of Aden (X. testigera profunda subsp. nov.), and one from the Kermadec Islands (X. neozelanica kermadecensis subsp. nov.). The fossil Xenophora known from Australia are reviewed and a new Upper Pliocene—Lower Pleistocene subspecies (X. flindersi ludbrookae subsp. nov.) and an unnamed Upper Cretaceous species are described.
The shell, and where known the radula, operculum and anatomy, are described for each species. The distribution and synonymy of each species is also given in detail. All of the species group names of fossil Xenophota are listed (Appendix, with J. Cooper).
Fossil species occurring outside Australia are not revised with the exception of a few which have relevance to the taxonomy of Recent species.