CPIE Project

Page P8


      Azolla and Pistia at Kawai Nui. Photo by Eric GuintherAQUATIC FERNS   Filicopsida 

      Figure 1. Deep red-tinged Azolla fern growing mixed with water lettuce, floating on the water surface of a slow flowing canal

      A listing of Hawaiian aquatic and riparian ferns, arranged by taxa, is provided elsewhere in CPIE.

Photo by Brian Daniel taken Jan 27, 2003
Figure 2 (left). Aerial view of lower Lake Wilson (Wahiawa Reservoir) showing surface covered by Salvinia molesta. Photo by Brian Daniel.

83a (72) Azolla from Kawai Nui Marsh, Kailua Fronds (leaves of ferns) pinnately branched bearing two rows of crowded leaves, each only about 3 mm across and two-lobed. { Growing in clusters in quiet waters (see Figure 1). Leaves usually tinged with reddish-purple. Water fern


Azolla filiculoides Lam.
83b S. molesta in Inoa`ole Stream, Waimanalo Floating leaves in pairs, each leaf 1 to 2 cm long, distinctly folded or with a midrib. Leaf covered on both surfaces with stiff hairs, but hairs on upper surface branching into 2 to 4 strands that rejoin at the tips (see photo inset). A third leaf accompanies each floating pair, growing downward being highly dissected, filiform (root-like) in shape. { Grown in decorative ponds, recently naturalized. Giant salvinia


Salvinia molesta D.S. Mitchell
M. villosa at Lualualei, Oahu
Figure 3. Marsilea villosa, water fern, or `ihi`ihi is a very rare fern known from only a few sites on O`ahu. This plant grows in vernal (emphemeral) ponds in relatively dry, leeward areas. Endemic and listed as an endangered species.

© 2002 AECOS, Inc. [FILE: plant2.html]

Aquatic Plants: Ferns