Spirodela punctata
Content
Distribution
Africa present, America, Asia present, Asia-Tropical: Jawa (Jawa present); Malaya (Peninsular Malaysia present), Australasia, Indian Ocean in the Maldives present, Mahe Atoll present, New Caledonia present, Pacific: Fiji (Fiji present), Pacific Islands, Pacific Ocean present, Pahang present, South America present
Apparently rare in Africa and South America, common in Asia and Australia, in the Indian Ocean in the Maldives (Mahé Atoll), in the Pacific Ocean in New Caledonia and Fiji; in Malesia: Malay Peninsula (Pahang) and Java (west to east).
According to DAUBS (1965) introduced in America, but this must then have been before 1814 when G. W. F. MEYER recorded it from there already. According to GUPPY (1906) introduced in the Pacific islands. Dispersal by man has certainly given this species a wider distribution in recent time; it is e.g. not rare in the rice-fields in Italy. Also its obviously local occurrence in Malesia might point to introduction.
According to DAUBS (1965) introduced in America, but this must then have been before 1814 when G. W. F. MEYER recorded it from there already. According to GUPPY (1906) introduced in the Pacific islands. Dispersal by man has certainly given this species a wider distribution in recent time; it is e.g. not rare in the rice-fields in Italy. Also its obviously local occurrence in Malesia might point to introduction.
Notes
S. punctata is a very variable species; several of its characters show considerable variations in different localities. As a result of this there are some populations which are characterized by a certain peculiarity not occurring in other populations. In some collections from Java the number of roots is extremely large (up to 12!), in other areas the number of roots rarely exceeds 5. The plants from New Caledonia and Fiji are characterized by a much heavier pigmentation than in other areas. These characters vary independently of each other, and do not seem to be constant even within one collection.
It is thus understandable that F. VON MULLER (ex KURZ, 1867) on the grounds of a small number of collections came to recognize 3 species in this complex, and that HEGELMAIER (1868) distinguished 5 varieties within S. oligorrhiza (raised to the rank of species in his paper of 1895). My investigation of much more material than these authors had at their disposal leads, however, to the conclusion that these taxa all belong to a single species, S. punctata, in which they are linked by all possible transitions.
From BLANCO'S description of Lemna gibba it is obvious that the plant in question was in fact S. punctata. MERRILL () erroneously interpreted L. gibba 'BLANCO' as L. paucicostata (= L. perpusilld).
It is thus understandable that F. VON MULLER (ex KURZ, 1867) on the grounds of a small number of collections came to recognize 3 species in this complex, and that HEGELMAIER (1868) distinguished 5 varieties within S. oligorrhiza (raised to the rank of species in his paper of 1895). My investigation of much more material than these authors had at their disposal leads, however, to the conclusion that these taxa all belong to a single species, S. punctata, in which they are linked by all possible transitions.
From BLANCO'S description of Lemna gibba it is obvious that the plant in question was in fact S. punctata. MERRILL () erroneously interpreted L. gibba 'BLANCO' as L. paucicostata (= L. perpusilld).
Citation
Engl. 1886 – In: Bot. Jahrb.: 448
OHWI 1965: Fl. Japan: 264
SCHWARZ 1928 – In: Fedde, Rep. 24: 80
MITRA 1958 – In: Fl. Pl. E. India: 86
BLANCO 1845: Fl. Filip., ed. 2: 468
DAUBS 1965: Monogr. Lemnac.: 15
DAUBS 1965: Monogr. Lemnac: 14-15
NAVES 1882: Novis. App.: 296
NAVES 1882: Novis. App.: 296
CLARK & THIERET 1968 – In: Mich. Bot.: 69
Benth. 1878 – In: Fl. Austr.: 163
HARTOG & PLAS 1970 – In: Blumea: 360
PRAIN 1903 – In: Bengal Pl.: 841
Hook.f. 1893 – In: Fl. Br. Ind.: 557
GUILLAUMIN 1959 – In: Mém. Mus. Hist. Nat. Paris n.s.: 189
GUPPY 1906: pp. 407-408. – In: Observ. Nat. Pac.
F. M. BAILEY 1902 – In: Queensl. Fl.: 1700
HEGELM. 1895 – In: Bot. Jahrb.: 287
BLACK 1948: Fl. S. Austr., ed. 2: 172
MCCANN 1942 – In: J. Bomb. Nat. Hist. Soc.: 157
GREENWOOD 1943 – In: Proc. Linn. Soc.: 104
BLANCO 1879 – In: Fl. Filip., ed. 3: 78
PARHAM 1964: Pl. Fiji Is.: 268
MCCOMB & MCCOMB 1967 – In: J. R. Soc. W. Austr.: 107
BACK. & BAKH.f. 1968 – In: Fl. Java: 127
GUILLAUMIN 1948: Fl. Nouv.-Caléd.: 48
MIKI 1934 – In: Bot. Mag. Tokyo: 333
KURZ 1962 – In: Mém. Mus. Hist. Nat. Paris n.s.: 213