Blyxa Noronha ex Thouars

This genus is accepted, and its native range is Tropical & Subtropical Old World.


Hydrocharitaceae, David Simpson. Flora of Tropical East Africa. 1989

Morphology General Habit
Dioecious (perhaps rarely monoecious) or hermaphrodite, submerged, freshwater, annual or perennial herbs
Morphology Roots
Roots simple, adventitious
Morphology Stem
Stems corm-like or elongate and rhizomatous or stoloniferous, or erect Leaves sessile, spirally arranged, radical or cauline, linear to elliptic, acuminate to obtuse, attenuate towards apex, patent, spreading or erect, flaccid, translucent, with up to 28 longitudinal veins; margins green, denticulate, at least towards the apex, the teeth usually patent
Morphology Leaves Stipules
Stipules 0
Morphology Leaves
Nodal scales 2 per leaf, narrowly triangular to triangular, with entire margins
Morphology Reproductive morphology Inflorescences Bracts
Spathe solitary in leaf-axil, sessile or pedunculate, cylindric, 2-lobed at the apex, somewhat translucent, 2–6-veined, with 1–2(–22) flowers
Morphology Reproductive morphology Flowers
Male flowers long-pedicellate, remaining attached to the plant at anthesis; ♀ and hermaphrodite flowers sessile or subsessile Flowers unisexual or bisexual
Morphology Reproductive morphology Flowers Calyx
Sepals 3, linear to linear-lanceolate, acute or cucullate, erect and often forming a tube at anthesis.
Morphology Reproductive morphology Flowers Corolla
Petals 3, filiform to lanceolate, acute to obtuse, papillose, often erect
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens 3 (in hermaphrodite flowers) 6 or 9, in whorls of 3; anthers erect, 4-thecous, latrorsely or introrsely dehiscent; filaments filiform; staminodes (in hermaphrodite flowers only) 3, rudimentary or absent
Morphology Reproductive morphology Flowers Gynoecium Pistil
Ovary of 3 carpels, narrowly cylindric, 1-locular, placentation parietal; ovules numerous, anatropous; perianth-tube filiform or narrowly cylindric, carrying perianth to the water surface; styles 3; stigmas 3, simple, linear, papillose on adaxial surface
Morphology Reproductive morphology Fruits
Fruit elongate, narrowly cylindrical, disintegrating at maturity
Morphology Reproductive morphology Seeds
Seeds numerous, narrowly ellipsoid, ellipsoid or ovoid, smooth, tuberculate, winged, ribbed or spiny.

Native to:

Andaman Is., Angola, Assam, Bangladesh, Borneo, Burundi, Cambodia, Caroline Is., Central African Repu, China North-Central, China South-Central, China Southeast, East Himalaya, Guinea, Guinea-Bissau, Hainan, India, Japan, Jawa, Korea, Madagascar, Malaya, Mali, Maluku, Manchuria, Mozambique, Myanmar, Nansei-shoto, Nepal, New Guinea, Northern Territory, Philippines, Queensland, Senegal, Sierra Leone, Sri Lanka, Sulawesi, Sumatera, Taiwan, Tanzania, Thailand, Vietnam, West Himalaya, Western Australia, Zambia, Zaïre

Introduced into:

Italy, Louisiana, Mississippi, Portugal

Blyxa Noronha ex Thouars appears in other Kew resources:

Date Reference Identified As Barcode Type Status Has image?
Edwards, P.J. [4054], New Guinea 70464.000 No

First published in Gen. Nov. Madagasc.: 4 (1806)

Accepted by

  • Govaerts, R.H.A. (2011). World checklist of selected plant families published update Facilitated by the Trustees of the Royal Botanic Gardens, Kew.


Flora of West Tropical Africa

  • F.T.A. 7: 6.
  • Gen. Nov. Madag. 4 (1806)

Flora of Tropical East Africa

  • Cook & Lüönd in Aquat. Bot. 15: 1 (1983)
  • Gen. Nov. Madag.: 4 (1806)
  • Rich. in Mém. Cl. Sci. Math. Phys. Inst. France, 1811(2): 19, 63, 77 (1812, published 1814)

  • Flora of Tropical East Africa

    Flora of Tropical East Africa

  • Herbarium Catalogue Specimens

  • Kew Backbone Distributions

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at and
    © Copyright 2017 World Checklist of Selected Plant Families.

  • Kew Names and Taxonomic Backbone

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at and
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families.