Cyttaria darwinii is a member of the genus Cyttaria, and grows abundantly as a parasite on the Southern Beech, Nothofagus. Darwin first collected them in his voyage to the Patagonia on the Beagle. The fruiting bodies, or reproductive structures, of C. darwinii are vivid orange or whitish globes, described by Darwin as “the colour of the yolk of an egg”, with varying sizes “from that of a bullet to that of a small apple”. He compares the gelatinous interior to “vermicelli pudding”. They grow from the host beech in groups off of stems. These golf ball-like fruiting bodies have mucous-like fluid inside that dries as the balls age. In the Tierra del Fuego, they are commonly used as food.
The description of the genus Cyttaria was first published in the Transactions of the Linnaean Society, Volume 19, in 1841. Because of Cyttaria’s close relationship to its host and the remarkable geographic distribution of Nothofagus, this genus is of particular interest as a system to study host-parasite relationships in a biogeographic framework.