Alsophila dregei (Kunze) R.M.Tryon

Plants terrestrial. Caudex stout, erect, simple, to 3 m tall, to 450 mm in diameter, densely covered with adventitious roots. Fronds to 30 per plant, caespitose, arching, to 2.2 m long; stipe greenish-brown, adaxially shallowly sulcate, variously tuberculate, to 410 mm long, to 15 mm in diameter, proximally densely scaled, scales firmly chartaceous, castaneus, sessile, subulate, cordate, margins short-fimbriate, apical cell not differentiated, to 25 mm long, to 5.5 mm wide, higher up closely set with stramineous to ferrugineous hairs of two kinds; 2-celled hairs with the apical cell much enlarged and variously shaped, and pluricellular, irregularly branched hairs of which the apical cell is not differentiated, to 0.6 mm long; lamina proximally anadromous, catadromous distally, elliptic, to 2-pinnate-pinnatifid, to 2 m long, to 700 mm wide, with up to 18 petiolated pinna pairs; rachis brown, often variously tuberculate, adaxially shallowly sulcate, initially set with scales and hairs similar to those on the stipe, glabrous later; pinnae petiolate, petiole to 5 mm long, alternate, overlapping, 1-pinnate-pinnatifid, oblong-acute to lanceolate, to 430 mm long, to 150 mm wide, with up to 20 pinnule pairs; pinna-rachis terete, initially closely set with ferrugineous hairs similar to those on the rachis; pinnules sessile, firmly herbaceous, pinnatifid, oblong-acuminate, to 80 mm long, to 24 mm wide, adaxially initially set with simple, pluricellular hairs along the costa and costule, abaxially closely set with scales and hairs along the costa, costule and veins, scales and hairs thinly chartaceous, ferrugineous, sessile, ovate, fimbriate, hairs simple or branched, to 1.5 mm long, to 0.4 mm wide; costa adaxially raised, pronounced abaxially; segments linear-acute to linear-obtuse, often somewhat falcate, shallowly dentate to crenate, to 10 mm long, to 3 mm wide; aerophores pale brown, in short lines dorsilaterally along the stipe and rachis. Venation evident, pinnately branched in the segments, vein branches once or twice forked, ending in the margin. Sori up to 9 pairs per segment, circular, often confluent at maturity, at a vein fork or inframedially on an acroscopic vein branch; receptacle raised, paraphysate, paraphyses simple, pluricellular, uniseriate, apical cell not differentiated; sporangium short-stalked, simple, laterally attached, capsule obtriangular in lateral view, annulus complete, with (17-)19(-20) indurated annulus cells; indusium inferior, cupuliform, surrounding receptacle base. Spores 16 per sporangium, brown, tetrahedral, trilete, papillate, exospore (38-)40.5(-44) µm in equatorial diameter.