Blechnum australe L.

Plants terrestrial or epilithic. Rhizome short-decumbent, to 4 mm in diameter, set with roots, crowded stipe bases, and scales, stoloniferous, stolons to 90 mm long, to 2 mm in diameter, thickening towards the apex, proximally with few roots and widely spaced fronds, fronds crowded towards the apex, scales chartaceous to crustaceous, castaneous, adnate, lanceolate to narrowly ovate, cordate, margins irregularly set with outgrowths terminating in an oblong thin-walled cell, apex terminates in an oblong thin-walled cell, to 7 mm long, to 1.5 mm wide. Fronds erect to arching, dimorphic, fertile generally overtop the sterile, sterile to 540 mm long, fertile to 560 mm long; stipe firm, proximally castaneous, stramineous higher up, adaxially sulcate, sterile to 140 mm long, to 1.2 mm in diameter, fertile to 150 mm long, to 1.2 mm in diameter, initially sparsely scaled, glabrous with age, scales chartaceous, ferrugineous to stramineous, sessile, lanceolate to ovate, cordate to cordate-imbricate, margins irregularly set with outgrowths terminating in an oblong thin-walled cell, apex terminates in an oblong thin-walled cell, to 6 mm long, to 1.3 mm wide; lamina 1-pinnate, sterile narrow elliptic, to 395 mm long, to 80 mm wide, fertile narrow elliptic, to 410 mm long, to 80 mm wide; rachis adaxially shallowly sulcate, sulcus not open to that of the costa, pronounced abaxially, variously set with scales, hairs, and glands, scales chartaceous, ferrugineous to stramineous, filiform, apex terminates in an oblong thin-walled cell, to 3 mm long, to 0.2 mm wide, hairs 2-celled, apical cell enlarged and thin-walled, glands cylindrical, to 0.3 mm long; pinnae firmly herbaceous, attenuate towards the apex, basal pinnae gradually reduced, sessile, adaxially glabrous or variously set with unicellular cylindrical glands similar to those on the rachis, abaxially sparsely set with filiform scales along the costa, often also closely set with cylindrical glands, sterile oblong-acute, often falcate, truncate to cordate, often acroscopically auricled, mucronate, margins with minute transparent teeth, to 43 mm long, to 9.5 mm wide, fertile linear, auriculate, mucronate, often falcate, to 37 mm long, to 2.5 mm wide; costa adaxially shallowly sulcate, pronounced abaxially. Venation evident or obscure, forked, in the sterile frond the free branches end near the margin in an enlarged apex; in the fertile frond the veins form a near-marginal vascular commissure with short excurrent veins extending from it. Sori linear, extending most of the pinna length; indusium firm, brown, linear, repand; sporangium long-stalked, simple, 3-seriate below capsule, capsule broadly elliptic in lateral view, with (12-)13(-14) indurated annulus cells, epistomium 4(-5)-celled, hypostomium 4(-5)-celled. Spores elliptic, monolete, with low, irregular verrucae, (36-)39.3(-42) x (26-)28(-32) µm.