Crypteronia shares its key embryological features with other genera of Crypteroniaceae and the order Myrtales. In common with Axinandra, it has such distinctive features as an ephemeral endothecium and a nucellar tissue that soon disintegrates. Crypteronia differs from Axinandra, however in seed morphology and in having neither an endothelium nor the associated secondary multiplication of the inner integument. Although embryological evidence supports a relatively close relationship between Crypteronia and Axinandra, it seems likely that these genera are more distantly related than is indicated by their vegetative features. Nevertheless, their continued placement within a single family is consistent with our new evidence.