Scientific name: Callitriche stagnalis Scop.
Common name: Common Water-starwort

Description
Habit: An aquatic or terrestial annual or perennial, variable.
Stems: Submerged, floating, creeping or terrestial.
Leaves: Opposite, undivided; all leaves oval, shortly stalked, 5-9 mm wide, but terrestial leaves smaller; upper leaves forming a floating terminal rosette.
Flowers: Small, monoecious, submerged or on water surface, without perianth, axillary; male flowers with 1 stamen, 0.5-2 mm; female flowers with 4-celled ovary.
Fruits: A group of 4 1-seeded nutlets, orbicular, 1.6-1.8 mm, as long as wide, with wing; styles erect or spreading when terrestial, not forming if submerged.

Note: fruiting material is vital for identification.

Habitat: Ponds, ditches and streams.
Distribution: Rare on the limestone, very frequent elsewhere.

Native status: Native
Of conservation interest: No

Family Callitrichaceae
Genus Callitriche
Species Callitriche stagnalis

Scientific synonyms and common names

Common Water-starwort [English]
Water-starwort, Common [English]

Stace, C. (1997) New Flora of the British Isles. Cambridge University Press, The Bath Press, UK.

Webb, D. A. and M. J. P. Scannell (1983) Flora of Connemara and the Burren. Royal Dublin Society and Cambridge University Press, Cambridge, UK.

Webb, D. A., J. Parnell and D. Doogue (1996) An Irish Flora. Dundalgan Press, Dundalk.

You can continue searching for Callitriche stagnalis on one of these Web sites:

Fauna Europaea (animals) | IOPI (plants) | NCBI (genetic)

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