Polycarpon tetraphyllum, commonly known as four-leaved allseed (also fourleaf allseed or fourleaf manyseed), is a plant of the family Caryophyllaceae. An annual herb growing to 15 cm in height, it is found on sandy soils, in coastal areas and on wasteland. Native to Europe, it is also naturalised in parts of North America, Australia and elsewhere. It is rare in Britain, except in the Scilly Isles.
Description
Polycarpon tetraphyllum is a prostrate, herbaceous, annual plant. The stems produce many branches, and leaves are obovate and glabrous.[3][4]
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The inflorescence consists of loose clusters of many small flowers at the end of each stem. The seeds are rounded and 0.4 - 0.5 mm long.[3][4]
Distribution and habitat
Polycarpon tetraphyllum is native to Southern Europe, Great Britain, the Mediterranean region, the middle east, the Indian subcontinent, and parts of tropical South America. It has been introduced to the Americas, Australia, New Zealand, and Southeast Asia.[1]
The plant tends to grow in disturbed, shady areas. It is commonly found as a weed growing in crevices in roads, gardens, and fields.[3][4][5]
Subspecies
Five subspecies are accepted.[1]
- Polycarpon tetraphyllum subsp. apurense (Kunth) Iamonico & C.A.Zanotti – eastern Colombia and Venezuela, Paraguay and northeastern Argentina
- Polycarpon tetraphyllum subsp. diphyllum (Cav.) O.Bolòs & Font Quer – Mediterranean basin, Canary Islands, and Madeira
- Polycarpon tetraphyllum subsp. dunense (P.Fraga & Rosselló) Iamonico – Balearic Islands (northern Menorca)
- Polycarpon tetraphyllum subsp. sauvagei (Mathez) Iamonico – Morocco
- Polycarpon tetraphyllum subsp. tetraphyllum – Great Britain, Germany, southern Europe, North Africa, northeastern tropical Africa, Western Asia, Arabian Peninsula, India, and Sri Lanka
References
- ^ a b c "Polycarpon tetraphyllum (L.) L. | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2021-08-04.
- ^ "Polycarpon tetraphyllum (L.) L." Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 14 March 2022.
- ^ a b c "Polycarpon tetraphyllum var. tetraphyllum". ucjeps.berkeley.edu. Retrieved 2021-08-04.
- ^ a b c "Factsheet - Polycarpon tetraphyllum". www.iewf.org. Retrieved 2021-08-04.
- ^ "PlantNET - FloraOnline". plantnet.rbgsyd.nsw.gov.au. Retrieved 2021-08-04.