Gunnera is the sole genus of herbaceous flowering plants in the family Gunneraceae, which contains 63 species. Some species in this genus, namely those in the subgenus Panke, have extremely large leaves. Species in the genus are variously native to Latin America, Australia, New Zealand, Papuasia, Hawaii, insular Southeast Asia, eastern Africa, and Madagascar. The stalks of some species are edible.
Taxonomy
Gunnera is the only genus in the family Gunneraceae. The APG II system of 2003 accepted this family and assigned it to the order Gunnerales in the clade core eudicots. The family then consisted of one or two genera, Gunnera and, optionally, Myrothamnus, the latter optionally segregated as a separate family, Myrothamnaceae. This represents a change from the APG system of 1998, which accepted two separate families, unplaced as to order. The APG III system and APG IV system accept the family Gunneraceae, and places Myrothamnus in Myrothamnaceae; both families are placed in the order Gunnerales in the core eudicots.
The genus Gunnera was named after the Norwegian botanist Johann Ernst Gunnerus. At first it was assigned to the family Haloragaceae, though that presented difficulties that led to the general recognition of the family Gunneraceae, as had been proposed about the beginning of the 20th century. In the meantime, in many publications it had been referred to as being in the Haloragaceae, variously misspelt (as for example "Halorrhagidaceae".) Such references still cause difficulties in consulting earlier works. However, currently Gunnera is firmly assigned to the monogeneric family Gunneraceae.
The type species of the genus is Gunnera perpensa L.
Gunnera is thought to be a rather ancient group, with a well-documented fossil history due to the presence of fossilized pollen spores, known by the palynotaxon Tricolpites reticulatus. It is a Gondwanan lineage, having originated in South America during the Cretaceous. The earliest fossilized pollen...