Hydriastele is a diverse and widespread genus of flowering plant in the palm family found throughout Australia and New Zealand, Melanesia, Polynesia, and Southeast Asia. It consisted of just nine species until 2004, when molecular research, supported by morphologic similarities, led taxonomists to include the members of the Gulubia, Gronophyllum, and Siphokentia genera. 48 species are now recognized, of which 38 are new combinations, two are new names and one is a new species. It is named in Greek, combining "hydriad", a water nymph in mythology, and "column".