Myriophyllum spicatum

Primary tabs

Myriophyllum spicatum


Aquatic. Middle and upper leaves entire, rarely pinnate, obtuse, mostly ovate to obovate, somewhat convex, sometimes spathulate or linear, and flat, 2-10 by 1-2 mm, patent, recurved in fruit. Flowers solitary in the middle and upper leaf-axils, the upper ones ♂, the lower ♀, in between often ☿, sessile. Fruit 1½-3 by 1½-3 mm, terete, very deeply and alternisepally 4-sulcate or deeply 4-cleft;


Africa and in the tropics present, Asia-Tropical: Philippines (Philippines present), Lake Lanao present, Mindanao present, N. Sumatra present, New Zealand absent, Toba Lake present, ubiquist on the northern hemisphere present
Almost ubiquist on the northern hemisphere, rare in Africa and in the tropics; in Malesia: N. Sumatra (Toba Lake) and Philippines (Mindanao: Lake Lanao, , n.v.). .
A record from New Zealand rests according to Miss R. MASON on an erroneous identification (LUCY B. MOORE, in litt.).


Very variable species. Reductions are not rare in the inflorescence, with the upper part strongly elongating, the lower part compact.
M. exalbescens FERN, is, apart from the stems which become whitish in drying, in no way otherwise qualitatively different from the European and Asiatic specimens of M. spicatum L. Specimens with ‘exalbescens’ characters (PATTEN, 1954; LÖVE, 1961) are found scattered all over the range of the species, not only in America.


OHWI 1965: Fl. Japan: 660
MEIJDEN 1969 – In: Blumea: 309
ALLAN 1940: Handb. Fl. New Zeal.: 285
Clarke 1878 – In: Fl. Br. Ind.: 433
RAYNAL 1966: p. 132. – In: Fl. Cameroun: fig.
TARDIEU-BLOT 1965 – In: Fl. Laos, Camb. & Vietn.: 125
Koord. 1912 – In: Exk. Fl. Java: 708
GUILLAUMIN 1920 – In: Fl. Gén. I.-C.: 717
PATTEN 1954 – In: Rhodora: 213
WILD 1961: Harmf. Pl: 42: t. 14d
Ridl. 1930: Disp.: 546
SUBRAMANYAM 1962: Aq. Ang.: 17
STEEN. 1932: Arch. Hydrobiol.: 316
LOVE 1961 – In: Rhodora: 139
SCHINDL. 1905 – In: Pfl. R.: 90
MAXIM. 1873 – In: Diagn. Pl.: 183
Merr. 1923 – In: En. Philip.: 221