Xerochrysum Bracteatum - Taxonomy

Taxonomy

French botanist Étienne Pierre Ventenat described the golden everlasting as Xeranthemum bracteatum in his 1803 work Jardin de Malmaison, a book commissioned by Napoleon's first wife Joséphine de Beauharnais to catalogue rare plants that she had collected and grown at the Château de Malmaison. The species name bracteatum is Latin, and refers to the papery bracts (often mistakenly called petals) of the flower heads. Henry Charles Andrews transferred it to the genus Helichrysum based on the morphology of its receptacle in 1805, and it was known as Helichrysum bracteatum for many years. Leo Henckel von Donnersmarck described it as Helichrysum lucidum in 1806, and Christiaan Hendrik Persoon as Helichrysum chrysanthum in 1807. It was given the name Bracteantha bracteata in 1991, when Arne Anderberg and Laurie Haegi placed the members that are known as strawflowers of the large genus Helichrysum into a new genus Bracteantha, and designated B. bracteata as the type species. However, they were unaware that Russian botanist Nikolai Tzvelev had already placed X. bracteatum in the new, and at the time monotypic, genus Xerochrysum the previous year. This name was derived from the Greek words xeros "dry", and chrysum "golden", likely relating to the nature of the distinctive bracts. There was confusion for a decade with Bracteantha appearing in literature and the horticultural trade until it was clarified in 2002 that the latter name took precedence. Strawflower is the popular name for X. bracteatum in Europe, while in Australia it is known as an everlasting or paper daisy. An alternate name in 19th-century Europe was immortelle. X. bracteatum itself is very variable and may represent several undescribed species. Alternately, the Tasmanian species Xerochrysum bicolor may be combined with it in future taxonomic revisions.

Xerochrysum bracteatum and its relatives belong to the Gnaphalieae or paper daisies, a large tribe within the daisy family Asteraceae. However, a 2002 molecular study of the Gnaphalieae has indicated the genus Xerochrysum is probably polyphyletic, as the two species sampled, X. bracteatum and X. viscosum, were not closely related to each other. Xerochrysum bracteatum has been recorded hybridizing with X. viscosum and X. papillosum in cultivation, and possibly also Coronidium elatum and C. boormanii.