The white-faced heron was
formally described in 1790 by the English ornithologist
John Latham. He placed it with the herons in the genus
Ardea and coined the
binomial name Ardea novaehollandiae. Latham based his account on the "white-fronted heron" that had been described and illustrated in 1789 by the first Governor of New South Wales
Arthur Phillip in his book
The Voyage of Governor Phillip to Botany Bay. It was historically considered to be closely related to
Ardea but for some time it was placed in its own genus—
Notophoyx—because of the absence of the plumes typical in that genus. Similarly, Swedish naturalist
Kai Curry-Lindahl felt the species was a dwarf member of the genus
Ardea.
Robert B. Payne and Christopher J. Risley placed the white-faced heron in the genus
Egretta due to its skeletal anatomy resembling egrets more than
Ardea herons. They noted that Bock had not given reasons why he had placed the species in
Ardea, and felt its closest relative was the
little blue heron (
Egretta caerulea) on account of plumage and skull similarities. Using DNA-DNA hybridization in a 1987 study, Frederick Sheldon confirmed the white-faced heron was a member of the egret clade. Subspecies
E. n. novaehollandiae and
E. n. parryi in Australia,
E. n. nana from New Caledonia and
E. n. austera from
Irian Jaya have previously been described, but are now not recognised taxonomically. ==Description==