Common names: None

Family: Hydrocharitaceae

Could be confused with: Eriocaulon, Najas, Nechamandra, Vallisneria.

Native distribution: West Africa to Australia.

Species commonly cultivated for the aquarium and/or pond plant industry:
Blyxa alternifolia (Miq.) Hartog
B. aubertii Rich. var. aubertii C.D.K. Cook & Lüönd (Madagascar to Japan to Australia)
B. aubertii Rich. var. echinosperma (C.B. Clarke) C.D.K. Cook & Lüönd (India to Australia)
B. japonica (Miq.) var. alternifolia (Miq.) C.D.K. Cook & Lüönd (Malaysia to Indonesia)
B. japonica (Miq.) var. japonica (Miq.) Asch. & Gürke (India to Japan to Papua New Guinea)
B. novoguineensis Hartog. (Papua New Guinea)
B. octandra (Roxb.) Planch. ex Thwaites (India to Australia)

Adventive distribution: Blyxa aubertii var. aubertii is introduced into Louisiana (United States) while B. japonica var. japonica is established in rice growing areas in northern Italy.

Weed status: Often found in rice fields but generally not considered a serious weed.

Habit: Submersed rosette or stem plant.

Brief description: Perennial or annual, monoecious or dioecious, rarely stoloniferous. Stem contracted or elongated. Leaves spirally arranged in rosette or opposite on elongate stem, sessile, linear to lanceolate, ribbon-like, venation parallel, midvein prominent; margin finely serrate. Inflorescence solitary or many-flowered, subtended by tubular spathe formed from two fused bracts, sessile or distinctly pedunculate. Flowers bisexual or unisexual, female flower sessile, male pedicellate; sepals 3, distinct, elongate; petals 3, white (rarely reddish), linear to filamentous, flaccid, fringed. Flower opens at or above water surface, pollinated by insects, or remains closed below water surface and is self-fertilized (cleistogamous). Seeds with longitudinal rows of tubercles or spines. Dispersal by seed, stolons or stem fragments.

Natural habitat: Ponds and streams.

Additional comments: A widely distributed genus containing eleven species from Africa to Australia; four species in Africa, one in Madagascar and six in warmer regions of Asia to Australia.