Flora of New Zealand Series

parrot's feather

Stout, glabrous, dioecious herb. Stems to 2 m long, 4-5 mm diam. near base, glaucous, rooting from lower nodes. Lvs all whorled, slightly dimorphic. Submerged lvs in whorls of (4)-5-6, (17)-35-45 × (4)-8-15 mm, oblanceolate or oblong with rounded apex, pectinate; pinnae 25-30, to 7 mm long, linear-subulate. Aerial lvs in whorls of (4)-5-6, (15)-25-35 × (4)-7-8 mm, narrowly oblanceolate or oblong with rounded apex, pectinate, glaucous, ± erect near apex; pinnae (18)-24-36, to 5.5 mm long, linear-subulate, slightly incurved. Base of aerial lvs with numerous hydathodes. Fls solitary in the axils of upper aerial lvs which are almost identical to other aerial lvs. Bracteoles 1.2-1.5 mm long, subulate, sometimes almost 3-fid. ♂ fls not seen in N.Z. ♀ fls with pedicel c. 0.2-0.4 mm long; sepals 0.4-0.5 × 0.3 mm, deltoid, white, denticulate with 1-several teeth; petals 0; ovary 4-ribbed between sepals. Fr. not seen.

N.: scattered localities from Auckland to the Wairarapa and S. Manawatu, particularly common in Auckland and Waikato Provinces; S.: one collection with submerged lvs only from Kaiapoi R. (N. Canterbury) is probably referable to M. aquaticum.

S. America 1970

Aerial or submerged in lake margins and slowly flowing rivers.

FL erratic, Sep-Feb.

Parrot's feather was presumably originally introduced as an indoor or outdoor aquatic plant. It often roots near banks in shallow water and stems readily become detached and drift to form large floating mats in deeper water; in this way new populations are easily formed by vegetative reproduction. It has been previously known in N.Z. as M. brasiliense.