All Floras      Advanced Search
Page 3 Login | eFloras Home | Help
Pakistan | Family List | Hydrocharitaceae | Hydrilla

Hydrilla verticillata (L. f.) Royle, Bot. Himal. t. 376. 1839. Hook. f., l.c.; Hartog in van Steenis, Fl. Males. 1(5): 385. fig. 1-3. 1957; Jafri, Fl. Kar. 11. fig. 8. 1966; Gandhi & Ramamoorthy in Saldanha & Nicolson, Fl. Hassan Dist. 634. 1976; Cook & Luond, Aq. Bot. 13: 485-504. 1982.


  • Hydrilla ovalifolia Rich.
  • Hydrilla polysperma Blatter
  • Serpicula verticillata Linn. f.
  • Vallisneria verticillata Roxb.

    Caulescent, glabrous, profusely branched freshwater herb with 5-50 mm long internodes and fibrous roots at some nodes. Leaves oblong-linear to lanceolate, (8-) 10-40 (-50) mm long, (1-) 2-3 mm wide, green, margin serrate-dentate, apex acute-apiculate; nodal scales 2, axillary, membranous with orange brown cilia on margin. Male spathe 1.25-1.50 mm long, bursting open to liberate male flower, beset with subulate appendages. Male flower: sepals reflexed, 1.5-3 mm long; petals linear-spathulate, equalling the sepals, patent or reflexed, obtuse; stamens with minute filaments. Female spathe c. 5 mm long, reddish-brown striped, bidentate. Ovary oblong, 3.4 mm long, with 1.5-10 cm long slender rostrum. Fruit ± terete. 5-7 mm long. Seeds dark brown, c. 2.5 mm long.

    Fl. Per.: October-January.

    Lectotype: “Habitat in India”, Herb. Linn. 1106. 1 (LINN).

    Distribution: Gregarious in ditches, pools, lakes, wet ricefields and slow-running water streams in S.E. Europe, Africa, Asia and Australia from sea level to 6000'; introduced in America and elsewhere.

    The plant is eaten by some fresh water fish and may be used as manure wherever it occurs in large quantities. It becomes a serious menace to navigation in large lakes and in irrigation canals as it reduces the rate of flow of water.


    Related Objects  
  • Illustration (M. Rafiq)
  • Illustration

    Flora of North America  
  • Distribution Map
  • Map

  •  |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |