Common names: 'iwa'iwa, 'iwa'iwa hawai (P. & E.), 'iwa 'iwa kahakaha (striped 'iwa 'iwa) (P. & E.), maidenhair fern, Venus' hair fern

Indigenous

Latin capillus, hair,+ venereus, of Venus.

Plants delicate, terrestrial or epipetric on shady banks. Rhizomes short-creeping, covered with tan scales. Fronds erect to spread-ing, 15-50 em long. Stipes dark brown to purplish black, glabrous, shiny. Blades 1-to 3-pinnate, regularly pinnately divided, lanceolate to ovate. Ultimate segments fan-shaped, membranous, lower margins wedge-shaped with centrally attached pinnule stalks, outer margins rounded, finely toothed, often shallowly to deeply irregularly lobed. Veins extending into marginal teeth, except for those ending in sari. Sori 3-7 per segment, bar-shaped at tips of lobes.

Occasionally found on shaded rock banks, coastal seeps, and in sea caves (Kaua'i and Moloka 'i) from near sea level to 430 m, all major islands and Ni 'ihau.

Adiantum capillus-veneris is uncommon to rare in Hawai'i and is known from only one location on O'ahu. Hawai 'i's only native Adiantum is also distributed worldwide in tropical or subtropical regions and is commonly grown in horticulture throughout the world. It is becoming increasingly scarce in Hawai 'i, but because its habitat is different from that of the more aggressive, introduced A. raddianum, there is probably not much competition between the two.

The dark stipes ofthis species were woven into !au hala mats to create designs. 'A 'ohe i ana iho ko 'u makemake i na 'iwa'iwa o ka ua o Ha'ao. (My desire is not satisfied for the maidenhair ferns in the Ha'ao rain.) (Ha'ao rain was the name of a rain at 'Au'aulele, Ka'ii and at Nu'uanu, O'ahu [Pukui and Elbert 1986].)

Adiantum capillus-veneris may be recognized by its fan-shaped pinnae and pinnules, veins that end in marginal teeth, and particularly by the bar-shaped sori on the lobe tips.