User:Semudobia/Caltha sagittata

Caltha sagittata, Arrow-leaved Marigold, is a perennial herbaceous plant belonging the Buttercup family native to Chile, the Falkland Islands, Argentina and in the Andes North to Lake Titicaca.

Description
As suggested by both the english and scientific names the leaves are sagittate, i.e., shaped like arrow-heads.

Flowers are white to cream with 5-8 tepals and about 3cm in diameter.

Taxonomy
C. sagittata was described by Cavanilles from specimens collected on Saunders Island in the Falkland Islands in 1799. When de Candolle revised the genus in 1817 he divided it into two sections, Caltha and Psychrophila, the latter including all species of the genus found in the Southern Hemisphere. In some works the latter section is raised to generic rank, but phylogenetic analysis of the DNA of several species in the genus indicated that whilst Psychrophila is itself monophyletic excluding it from the genus Caltha would make the latter a paraphyletic taxon.

Phylogeny
The South American species of Caltha diverged from an ancestral line lcocated in the Northern Hemisphere around 55 million years ago.

Habitat
It is a frequent component of sphagnum bogs and mires of Tierra del Fuego.

Images and Illustrations

 * Painting by Sydney Parkinson from the HMS Endeavour expedition from collections of the Natural History Museum.
 * Original description
 * Flickr