Home / Anomalous_Items / Aquatic_Macrophytes / Submerged_Leaves / Najas
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Name derivation:
Najas - Greek, a river nymph, naias. Common names ‘brittle water-nymph’, ‘eutrophic water-nymph’, ‘Holly-leaved Naiad’.
Classification:
Najas Linneaus 1753; at least 37 species descriptions are currently accepted taxonomically. Order Alismatales; Family Hydrocharitaceae, or Najadaceae (until 1997). Monocot.
Morphology:
Thin stems up to 1 mm in diameter. Sheathed leaves are oppositely arranged and have serrulate martings, 7-15 teeth on each side, and 0.5-3.5 cm long. Dioecious (N. marina), incomplete flowers 1-2 flowers per axil, up to 4 mm long with prominence of females in the U.K.(10x more than males)(Handley and Davy 2000).
Similar genera:
Habitat:
Freshwater, to depths of 4-5 m. N. minor is native to Africa, Japan, India and central Europe, and intentionally introduced to Cayuga Lake, NYS USA in 1935. It’s now invasive in New England USA. [online].
References:
Handley, R.J., and A.J. Davy 2000. Discovery of male plants of Najas marina L. (Hydrocharitaceae) in Britain. Watsonia 23:331-334.