Synonym(s): Trichomanes aethiopicum Burm. f.; Asplenium cristatum sensu W. J. Rob., non Brack.; A. cuneatum sensu auct., non Lam.; A. furcatum sensu Hillebr., non Thunb.; A. praemorsum Sw.; A. rhipidoneuron W. J. Rob.; A. spathulinum Hook. var. furcellatum Hillebr.

'iwa 'iwa a Kane ("Kane's 'iwa'i"wa")

Indigenous

Latin, aethiopicus, in 1768 a general term for the entire African continent. The type material was described from a South African collection.

Plants small to medium-sized, terrestrial, occasionally epiphytic or epipetric. Rhizomes short-creeping to decumbent, 0.8-1.5 cm diam., heavily covered with dark brown, glossy, lanceolate scales with curly, some-times hairlike tips. Fronds closely set, erect or arching, (12-) 20-60 x 5-14 cm, not proliferous. Stipes about 1/2 frond length, dark brown, scales at base sparse, linear-lanceolate, dark brown. Blades 1-to 2-pinnate-pinnatifid, lanceolate, tips pinnatifid, acute; rachises and costae grooved, sparsely to heavily clothed with hairlike scales. Pinnae 6-16 pairs, short-stalked to adnate, suboppo-site to alternate. Ultimate segments adnate, fan-shaped (flabellate), especially aero-scopic basal segments, mostly with truncate tips, without central axis, very variable in shape, often laciniate, tips often lobed, distal margins with many small, obtuse teeth. Veins forked in fan shape without a central axis, ending in marginal teeth, minimally to not translucent. Sori 2-8 per segment, spreading in a fan shape, up to 1 cm long, some sori pericostal. Indusia wide, same color as frond.

Locally common in mesic to wet forests, shrublands, and occasionally in dry exposed areas, 305-1,950 m, all major islands. A com-pact, hairy, dwarf form with fronds 12-15 cm long grows on open lava flows or in cavities in exposed lava boulders on Maui and Hawai 'i.

This pantropical species is part of a wide-spread and extremely polymorphic Asplenium aethiopicum/praemorsum complex that so far has not been well delimited. If A. aethiopicum is considered to be pantropical, then A. praemorsum, a New World species, is a synonym. Further study may show that A. praemorsum is a valid species and that the Hawaiian plants may originate from the New World rather than from the Old World and Pacific A. aethiopicum.

Asplenium aethiopicum, a 1-to 2-pinnate-pinnatifid fern, is quite variable in pinna shape and segment width, but the fan-shaped ultimate segments are always a distinguishing feature.