Flora of New Zealand Series

Usually glabrous perennial, forming small to large patches; stems slender. Lvs 3-foliolate; leaflets sessile, glossy green or bronze-tinged, usually glabrous, very rarely with a few scattered hairs, broadly obovate-cuneate, (1)-3-6-(8) mm long, with 1-3 lobes and each lobe with 1-4 shallow crenate teeth; leaflets produced early in the growing season and leaflets of reduced plants often entire or with 2-3 shallow crenate teeth; petiole usually glabrous, very rarely with a few retrorse hairs near blade. Umbels simple, (1)-2-7-flowered; peduncles ± = lvs. Fls shortly pedicellate. Fr. glabrous, (1.5)-2-2.5 × (1)-1.2-1.8 mm, rounded on dorsal edge; ribs slightly engraved into surface of mature fr.

N.: C. montane areas; S.: montane areas, also lowland and coastal especially in W. and southern areas; St.: lowland and coastal.

Endemic.

Wet flushes in montane tussock grassland, swamps, lake and stream edges, sometimes with rhizomes and petioles permanently submerged.

This sp. has usually been included in N.Z. within a broad concept of H. tripartita, but is distinguished from that sp., in its strict sense, by its usually glabrous lvs, rounded lf-teeth, and the engraved mericarp ribs. Reduced plants of H. sulcata are difficult to distinguish from H. hydrophila.