''Ruppia maritima'' is an

aquatic plant Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...

species commonly known as beaked tasselweed, ditch grass, tassel pondweed and widgeon grass. Despite its

scientific name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

, it is not a marine plant; is perhaps best described as a

salt-tolerant Halotolerance is the adaptation of living organisms to conditions of high salinity. Halotolerant species tend to live in areas such as hypersaline lakes, coastal dunes, saline deserts, salt marshes, and inland salt seas and springs. Halophiles a ...

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. Although the term specifically excludes seawater and brackish water, it does include ...

species.Kantrud, H. A. (1991)
Classification and Distribution - Wigeongrass (''Ruppia maritima'' L.): A literature review.
U.S. Fish and Wildlife Service. The generic name ''Ruppia'' was dedicated by Linnaeus to the German botanist Heinrich Bernhard Ruppius (1689-1719) and the specific name (maritima) translates to "of the sea".

Distribution

It can be found throughout the world, most often in coastal areas, where it grows in

brackish water Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estua ...

bodies, such as

marsh A marsh is a wetland that is dominated by herbaceous rather than woody plant species.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p Marshes can often be found at ...

es. It is a dominant plant in a great many shoreline regions. It does not grow well in

turbid Turbidity is the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of water quality. Fluids can ...

water or low-oxygen substrates.Kantrud, H. A. (1991)
Habitat - Wigeongrass (''Ruppia maritima'' L.): A literature review.
U.S. Fish and Wildlife Service.

Description

''Ruppia maritima'' is a thread-thin, grasslike annual or perennial herb which grows from a

rhizome In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...

anchored shallowly in the wet substrate. It produces a long, narrow, straight or loosely coiled

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

tipped with two tiny flowers. The plant often self-pollinates, but the flowers also release

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...

that reaches other plants as it floats away on bubbles.Kantrud, H. A. (1991)
Development and Reproduction - Wigeongrass (''Ruppia maritima'' L.): A literature review.
U.S. Fish and Wildlife Service. The fruits are

drupe In botany, a drupe (or stone fruit) is an indehiscent fruit in which an outer fleshy part (exocarp, or skin, and mesocarp, or flesh) surrounds a single shell (the ''pit'', ''stone'', or '' pyrena'') of hardened endocarp with a seed (''kernel'') ...

lets. They are dispersed in the water and inside the digestive system of fish and waterbirds that eat them. The plant also reproduces vegetatively by sprouting from its rhizome to form colonies.

Taxonomy and nomenclature

On the basis of molecular phylogenetic analyses, a species complex, named ''R''. ''maritima'' complex, had been discerned, which was then extended to include eight lineages, or nine lineages. A lectotype for '' R. cirrhosa'' is designated and the name is shown to be a homotypic synonym of ''R. maritima''.Ito, Y., T. Ohi-Toma, C. Nepi, A. Santangelo, A. Stinca, N. Tanaka, & J. Murata (2017
Towards a better understanding of the ''Ruppia maritima'' complex (Ruppiaceae): Notes on the correct application and typification of the names ''R. cirrhosa'' and ''R. spiralis''
''

Taxon In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

'' 66: 167-171

Wetlands and wildlife

This plant and the epiphytic algae attached to the floating leaves can be an important part of the diet for selected herbivorous

waterfowl Anseriformes is an order of birds also known as waterfowl that comprises about 180 living species of birds in three families: Anhimidae (three species of screamers), Anseranatidae (the magpie goose), and Anatidae, the largest family, which in ...

species, but not important for predatory waterfowl that eat fish or invertebrate animals. In many areas, wetlands restoration begins with the recovery and protection of this plant.Kantrud, H. A. (1991)
Introduction - Wigeongrass (''Ruppia maritima'' L.): A literature review.
U.S. Fish and Wildlife Service.

References

External links