Helosciadium nodiflorum (L.) W.D.J.Koch

Procumbent to ascending, aquatic or amphibious perennial, rooting at lower nodes. Stems hollow, grooved, striate, up to 180 cm long. Basal lvs 1-pinnate, petiolate; leaflets in 2–8 pairs, ovate to lanceolate, serrate, sometimes lobed, particularly the terminal leaflet, 1–8–(12) cm long, sessile; stem lvs similar to basal, but uppermost often reduced to 3–5 leaflets. Umbel 2–4 cm diam., compound, subsessile or shortly pedunculate, lf-opposed; rays 4–14; bracts 0–2, linear to lanceolate; bracteoles 4–8, ovate-triangular. Fls numerous, white, 1–2 mm diam. Fr. ovoid, dark brown, 1.5–2.5 mm long; ribs light brown, slender or slightly thickened.

[From: Webb et al. (1988) Flora of New Zealand. Volume 4. as Apium nodiflorum (L.) Lag.]

Flowering: Nov.–Feb.