Alternanthera denticulata R.Br.
A. sessilis Hook. f. Fl. N.Z. 1, 1854, non R.Br. loc. cit.
Decumbent branching herb 10-50 cm. long, rooting at lower nodes; branchlets sparsely pubescent when young. Lvs ( 1 )-2-4-(5) cm. long, including short petioles; lamina narrow-lanceolate to narrow-oblong to obovate-oblong (all forms may occur on same plant), obtuse to subacute, minutely denticulate. Fls in densely placed axillary clusters 5-8-(10) mm. diam.; fls ± 3 mm. long. Tepals white, scarious, in 2 unequal series(the longer ± 3 mm. long, linear-lanceolate, acuminate; the shorter broader, ± 2.5 mm. long; perfect stamens 2-3. Utricle much compressed, ± 1·5 × 2 mm., light brown, broad-obcordate, margins thickened.
DIST.: N. Boggy areas from near North Cape to Auckland; local and mostly in waste places to Wellington.