''Littorella'' is a genus of two to three species of aquatic plants. Many plants live their entire lives submersed, and reproduce by

stolon In biology, stolons (from Latin '' stolō'', genitive ''stolōnis'' – "branch"), also known as runners, are horizontal connections between organisms. They may be part of the organism, or of its skeleton; typically, animal stolons are external s ...

s, but some are only underwater for part of the year, and flower when they are not underwater.

Classification

Molecular data show ''Littorella'' to be sister to the rest of the genus '' Plantago''. Thus, cladistics would allow it to be considered either as a separate genus or as part of ''Plantago''. Some researchers, particularly Rahn in the 1990s, have considered ''Littorella'' to be located within ''Plantago'', but this does not seem to be required given the molecular data and a closer look at morphology.

Species

*''

Littorella uniflora ''Littorella uniflora'' (vernacular name: (American) shoreweed) is a species of aquatic flowering plant native to the Azores, Morocco, most of Europe excluding the dry southeast, Iceland, and the Faroes. It prefers to live mostly submerged in nu ...

''. Found in Europe from Iceland to the Black Sea. *''

Littorella americana ''Littorella americana'' Is a species of flowering plant commonly called American shore plantain. It is a small aquatic plant native to Newfoundland and Nova Scotia to Minnesota. Description ''Littorella americana'' Is a monoecious (having sepa ...

'' from northern

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

. *''

Littorella australis ''Littorella'' is a genus of two to three species of aquatic plants. Many plants live their entire lives submersed, and reproduce by stolons, but some are only underwater for part of the year, and flower when they are not underwater. Classific ...

'' from patagonia, in southern Chile and Argentina, and the Falkland Islands Some authors have treated ''L. uniflora'' and ''L. americana'' to be one species, but molecular data show ''L. americana'' to be more closely related to ''L. australis'' than it is to ''L. uniflora'', which argues for recognizing three species. Other considerations, such as the wider range and more frequent flowering of ''L. uniflora'', also argue for separate species. It seems likely that the genus originated in Europe and first spread to North America, and from there to South America, with both events happening in the Pleistocene or later.

Distribution

The European species is found in a wide range of habitats, from arctic to Mediterranean. The North and South American species are found in a more limited range of temperate climates.

References

{{Authority control Plantaginaceae Plantaginaceae genera Taxa named by Carl Linnaeus