台灣植物誌 第二版 Flora of Taiwan, 2nd edition Vol. 1
37. AZOLLACEAE 滿江紅科
DEVOL, CHARLES E.
Small floating ferns; horizontal stem very short, vegetative reproduction rapid; roots borne singly or in groups, unbranched. Leaves imbricating, upper aerial lobe covered with papillae, often turning reddish in winter and in hot summer; with a cavity near base, containing Anabaena; lower submersed lobe only l cell thick. Sporocarps usually borne in pairs; microsporocarp globose, containing long stalked microsporangia; microspores imbedded in massulae; megasporocarp ovoid, smaller, containing a basal megasporangium above which may be a collar, and then 1 or 2 tiers of floats with an apical flagellate funnel-like zone.
A family of one genus.
1. AZOLLA Lam. 滿江紅屬
Characters of the family.
About seven species, only one in Taiwan.
1. Azolla pinnata R. Brown, Prod. Fl. Nov. Holl. 167. 1810; DeVol in Fl. Taiwan 1: 60. pl. 14. 1975. 滿江紅 Pl.211, Photo 76
Azolla imbricata (Roxb.) Nakai in Bot. Mag. Tokyo 39: 183. 1925.
Plants triangular, about 1 cm wide. Leaves trapezoidal; massulae bearing a few pointed trichomes on ventral side. Megasporangium warty, no collar, 2 tiers of floats (3 above, 6 below) and a terminal flagellated crown.
Distributed in Africa, Asia, Australia, Islands of Pacific and Taiwan. Known from nearly every county but not many collections have been made. Floating on ponds, paddy fields, and irrigation ditches.
TAIPEI: Neihu, Kuo 779; Shihlin, DeVol 7514. TAICHUNG: Tungshih, Kuo 3907. NANTOU: Chichi, Kao 3923. CHIAYI: Nanching, DeVol 7292. TAINAN: Mata, Morimoto 583. TAITUNG: Is. Lanyu, Huang 6432*.