Wolffia globosa
W. globosa (small) with Spirodela polyrrhiza (larger)
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Alismatales
Family: Araceae
Genus: Wolffia
W. globosa
Binomial name
Wolffia globosa
(Roxb.) Hartog & Plas

Wolffia globosa is a species of flowering plant known by the common names Asian watermeal and duckweed. It is native to Asia and is found in parts of the Americas and Africa, where it is an introduced species.[2] It grows in mats on the surface of calm, freshwater bodies, such as ponds, lakes, and marshes. It is a very tiny, oval-shaped plant with no leaves, stems, or roots. The body of the plant, a transparent green frond, is less than a millimeter wide. In one human experiment, processed W. globosa was reported to provide dietary protein and vitamin B12.[3]

Wolffia globosa has been described as the world's smallest flowering plant, at 0.1–0.2 mm (0.004–0.008 in) in diameter.[4][5]

Known in Thai as Pham (ผํา), it is a popular item in Thai cuisine, especially in Isan.[6]


  1. ^ Mani, S. (2011). "Wolffia globosa". IUCN Red List of Threatened Species. 2011: e.T177384A7426184. Retrieved 26 September 2022.
  2. ^ "Wolffia globosa (Roxb.) Hartog & Plas". Plants of the World Online. Royal Botanic Gardens Kew. 2022. Retrieved 5 February 2023.
  3. ^ Kaplan A, Zelicha H, Tsaban G, Yaskolka Meir A, Rinott E, Kovsan J, Novack L, Thiery J, Ceglarek U, Burkhardt R, Willenberg A, Tirosh A, Cabantchik I, Stampfer MJ, Shai I (December 2019). "Protein bioavailability of Wolffia globosa duckweed, a novel aquatic plant - A randomized controlled trial". Clin Nutr. 38 (6): 2576–2582. doi:10.1016/j.clnu.2018.12.009. PMID 30591380.
  4. ^ Lock, Helen (4 Sep 2013). "Rare bloom for Wolffia Globosa, the world's smallest flowering plant". The Daily Telegraph. London. Retrieved 25 Sep 2016.
  5. ^ "What is the smallest flower in the world? (Everyday Mysteries: Fun Science Facts from the Library of Congress)". www.loc.gov. Library of Congress. Retrieved 22 August 2019.
  6. ^ แกงไข่ผำ(สาหร่ายสไปรูลิน่า)สูตรและวิธีทำ