Scientific Name:
Zannichellia palustris L. (1753)
Vernacular Name(s):
Horned pondweed

Submerged summer-green herb. Rhizome to 1 mm. diam., to 10 cm. long; internodes 1–2 cm. Stems much-branched, mostly < 1 mm. diam., to 100 cm. long; internodes 2–4 cm. long between apparent whorls of lvs. Lvs c. 2–5 cm. × < 1 mm., narrow-linear, 1-nerved, entire except for minute teeth near acuminate tip. Infl. within swollen lf-bases. Anther at first almost sessile, filament later 3–5 mm. long, reaching level of stigma; connective excurrent in knob of spongy tissue. Carpels us. 3–4; style at first longer than ovary, about as long as widely flaring, thinly membr., funnel-shaped stigma. Fr. 2.5 × < 1 mm., curved, shortly stipitate, yellow, surmounted by c. 1 mm. of style remnant.

[From: Moore and Edgar (1970) Flora of New Zealand. Volume 2.]

Indigenous (Non-endemic)

Flowering: Dec.–Feb.; Fruiting: Jan.–May.

de Lange, P.J.; Rolfe, J.R.; Barkla J.W.; Courtney, S.P.; Champion, P.D.; Perrie, L.R.; Beadel, S.N.; Ford, K.A.; Breitwieser, I.; Schönberger, I.; Hindmarsh-Walls, R.; Heenan, P.B.; Ladley, K. 2018: Conservation status of New Zealand indigenous vascular plants, 2017. New Zealand Threat Classification Series. No. 22. [Naturally Uncommon]
de Lange, P.J.; Rolfe, J.R.; Champion, P.D.; Courtney, S.P.; Heenan, P.B.; Barkla, J.W.; Cameron, E.K.; Norton, D.A.; Hitchmough, R.A. 2013: Conservation status of New Zealand indigenous vascular plants, 2012. New Zealand Threat Classification Series 3. Department of Conservation, Wellington. [Naturally Uncommon]