Citation: Lam., Encycl. 1:343 (1783).

Derivation: Greek azo, to dry; ollyo, to kill; plants killed by drought.

Synonymy: Not Applicable

Common name: Azollas.

Description:
Plants ovate to triangular, usually 1-3 cm long, rapidly increasing by fragmentation; fronds in 2 rows, numerous, triangular, c. 1.5 mm long, imbricate, a bright red-brown to rose in open situations or green in more shaded places; sporangia borne on submerged lobes and bearing in the axils 2-4 megasporocarps or microsporocarps; microsporocarps ovoid or globular to 2 mm diam., covered by a transparent indusium, microsporangia 8-100, spherical, stalked; massulae (hardened mucilaginous masses in the sporangia, containing the microspores) 4-10, bearing few or many hooked or non-hooked septate or non-septate processes; microspores 32-64, occurring in groups within the massulae; megasporocarps conical, protected by a membranous indusium megaspores solitary in the megasporocarps.

Distribution:  Cosmopolitan; 6 species, 2 in Australia.

Biology: No text

Key to Species:

1. Roots simple	A. filiculoides 1.
1. Roots feathery	A. pinnata 2.

Author: Not yet available