Hymenophyllum obtusum Hook. & Am.

Common names: palai lau li'i (small-leaved palai)

Endemic

Latin obtusus, blunt, dull, alluding to the generally obtuse shape of the frond tips.

Plants delicate, epiphytic. Rhizomes thread-like. Fronds 3-9 x 0.7-2.5 cm. Stipes quite hairy, hairs brown to dark brown, branched or unbranched at base, often branched distally. Blades 2-pinnate to 3-pinnate-pinnatifid, variable in shape, compact, ovate to some-what lanceolate, membranous but somewhat stiff, appearing reddish brown because of hairs, tips obtuse, hairs abundant on veins, and margins, branching at base and distally. Pinnae linear, obtuse tipped, spreading from planes of rachises, resulting in a 3-dimensional quality, less than 1 mm wide. Veins dark, obscured by hairs. Sari marginal at tips of ultimate segments. Indusia extending from ultimate segment tips, very hairy.

Epiphytic on trees and logs in wet forests, 400-1,300 m, all major islands except Kaua 'i. Less common than Sphaerocionium lanceolatum. It is usually found on portions of tree trunks and logs protected from sun and wind.

Sphaerocionium obtusum may be distinguished from S. lanceolatum by its shorter, rounder, more compact, 3-dimensional fronds with the stipes and blades heavily clothed with hairs that branch both at the base and distally; the whole plant has a brownish, shaggy appearance.