''Marsilea'' is a genus of approximately 65 species of

aquatic Aquatic means relating to water; living in or near water or taking place in water; does not include groundwater, as "aquatic" implies an environment where plants and animals live. Aquatic(s) may also refer to: * Aquatic animal, either vertebrate ...

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

s of the family

Marsileaceae Marsileaceae () is a small family of heterosporous aquatic and semi-aquatic ferns, though at first sight they do not physically resemble other ferns. The group is commonly known as the "pepperwort family" or as the "water-clover family" becau ...

. The name honours Italian naturalist

Luigi Ferdinando Marsili Count (nobility), Count Luigi Ferdinando Marsili (or Marsigli, ; 10 July 1658 – 1 November 1730) was an Italian scholar and natural scientist, who also served as an emissary and soldier. Biography Born in Bologna, he was a member of an an ...

(1656–1730). These small plants are of unusual appearance and do not resemble common ferns. Common names include water clover and four-leaf clover because of the long-stalked leaves have four

clover Clovers, also called trefoils, are plants of the genus ''Trifolium'' (), consisting of about 300 species of flowering plants in the legume family Fabaceae originating in Europe. The genus has a cosmopolitan distribution with the highest diversit ...

-like lobes and are either present above water or submerged. It is worth clarifying that these plants are not clovers. The sporocarps of some

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

n species are very drought-resistant, surviving up to 100 years in dry conditions. On wetting, the gelatinous interior of the sporocarp swells, splitting it and releasing a worm-like mass that carries sori, eventually leading to germination of

spore In biology, a spore is a unit of sexual reproduction, sexual (in fungi) or asexual reproduction that may be adapted for biological dispersal, dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores fo ...

s and fertilization.

Uses

As food

Sporocarps of some Australian species such as ''

Marsilea drummondii ''Marsilea drummondii'' is a species of fern known by the common name nardoo. It is native to Australia, where it is widespread and common, particularly in inland regions. It is a rhizomatous perennial aquatic fern that roots in mud substrates an ...

'' are edible and have been eaten by Aborigines and early white settlers, who knew it under the name ngardu or nardoo. Parts of ''Marsilea drummondii'' contain an

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

which destroys

thiamine Thiamine, also known as thiamin and vitamin B1, is a vitamin – an Nutrient#Micronutrients, essential micronutrient for humans and animals. It is found in food and commercially synthesized to be a dietary supplement or medication. Phosp ...

(vitamin B₁), leading to brain damage in sheep and horses. During floods in the

Gwydir River Gwydir River (locally Australian English phonology, wɑe̯də, a major inland perennial stream, perennial river of the Barwon River (New South Wales), Barwon catchment within the Murray–Darling basin, is located in the Northern Tableland ...

basin 2,200 sheep died after eating nardoo. Three-quarters of the sheep that were affected did however respond to thiamine injections.

Thiamine Thiamine, also known as thiamin and vitamin B1, is a vitamin – an Nutrient#Micronutrients, essential micronutrient for humans and animals. It is found in food and commercially synthesized to be a dietary supplement or medication. Phosp ...

deficiency from incorrectly prepared nardoo likely resulted in the starvation and death of

Burke and Wills The Burke and Wills expedition (originally called the Victorian Exploring Expedition) was an exploration expedition organised by the Royal Society of Victoria (RSV) in Australia in 1860–61. The exploration party initially consisted of nine ...

. The leaves of ''

Marsilea crenata ''Marsilea crenata'' is a species of fern found in Southeast Asia. It is an aquatic plant looking like a four leaf clover. Leaves floating in deep water or erect in shallow water or on land. Leaflets glaucous, sporocarp ellipsoid, on stalks a ...

'' are part of the East Javanese cuisine of

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

, especially in the city of

Surabaya Surabaya is the capital city of East Java Provinces of Indonesia, province and the List of Indonesian cities by population, second-largest city in Indonesia, after Jakarta. Located on the northeastern corner of Java island, on the Madura Strai ...

. It is called Pecel Semanggi and is served with spicy peanut and sweet potato sauce.

Ornamental

A few species in the genus, such as ''

'', '' Marsilea exarata'', '' Marsilea hirsuta'', and ''

Marsilea quadrifolia ''Marsilea quadrifolia'' is a herbaceous plant found naturally in central and southern Europe, Caucasia, western Siberia, Afghanistan, south-west India, China, Japan, and Vietnam, though it is considered a weed in some parts of the United States, ...

'', are grown in aquaria.

Formerly placed here

*''

Salvinia natans ''Salvinia natans'' (commonly known as floating fern, floating watermoss, floating moss, or commercially, water butterfly wings) is an annual floating aquatic fern, which can appear superficially similar to moss. It is found throughout the world ...

'' (L.) All. (as ''M. natans'' L.)

Phylogeny

Molecular A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, ...

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

analysis of the genus ''Marsilea'' shows the following tree. This tree indicates that '' M. crenata'' is the same species (or a subspecies) of '' M. minuta'', and possibly '' M. fadeniana'' also. Additionally, this analysis contradicts reportsTropicos.org. Missouri Botanical Garden. 25 Sep 2017 http://www.tropicos.org/Name/26602149 that '' M. polycarpa'' is a synonym for ''M. minuta'' Other species include: *'' Marsilea aethiopica'' Launert *'' Marsilea apposita'' Launert *'' Marsilea batardae'' Launen *'' Marsilea burchellii'' A.Braun *'' Marsilea condensata'' Bak. *'' Marsilea cryptocarpa'' Albr. & Chinnock *'' Marsilea fenestrata'' Launert *'' Marsilea globulosa'' Bouchart *'' Marsilea hickenii'' Herter *'' Marsilea latzii'' Jones *'' Marsilea megalomanica'' Launert *'' Marsilea pyriformis'' Bouchart *'' Marsilea quadrata'' Brown *'' Marsilea ×subangulata'' Brown *'' Marsilea subterranea'' Leprieur *'' Marsilea unicornis'' Launert *'' Marsilea vera'' Launert

References

*Mabberley, D.J. (1997). ''The Plant-Book''. Cambridge University Press. * Edmund Russow: ''Histologie und Entwicklungsgeschichte der Sporenfrucht von Marsilia.'' Dissertation. Dorpat 1871
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*Johnson 1986 Systematics of the New World species of Marsilea. Syst. Bot. Monog. 11:1–87.

* {{Authority control Aquatic plants Fern genera ja:デンジソウ