The genus Cryphaea comprises 30 species including two new species described from China after revisions. In this synopsis, the research history, morphology and anatomy, phylogeny, ecology, and phytogeography of Cryphaea are reviewed. The morphological and anatomical characters are discussed in detail. The variation range of each character is clarified. The group is speculated to have originated in West Gondwanaland (Africa-South America) around the Lake Cretaceous to early Tertiary (ca. 70-60 m.y. BP).