Dryopteris lewalleana Pic.Serm.

Plants terrestrial or epilithic. Rhizome short-decumbent, sparsely irregularly branched, to 21 mm in diameter, set with roots, closely spaced stipe bases and scales, the scales stramineous to ferrugineous, rarely atrocastaneous, chartaceous to thinly crustaceous, broadly attached, ovate-caudate to linear-acuminate, to 18 x 4 mm, cuneate to cordate, the margins entire, repand, or with a few widely spaced, uniseriate, multicellular hairs, and pyriform glands, the scale apex filiform, terminating in a uniseriate series of oblong cells. Fronds suberect to arching, to 1.3 m long; stipes proximally castaneous, stramineous to greenish higher up, proximally adaxially flattened, shallowly sulcate higher up, to 750 mm long, to 8 mm in diameter, proximally densely scaled, moderately to sparsely scaled higher up, the scales stramineous to ferrugineous, chartaceous, the larger scales broadly attached, to 25 x 6 mm, the smaller scales sessile or short-stalked, ovate to narrowly lanceolate, or filiform, cordate to cuneate, the margins entire or denticulate, often with a few widely spaced, multicellular hairs, and pyriform glands (which may also occur on the scale laminae), marginal hairs on the smaller scales are mostly confined to the basal region, the scale apex filiform, terminating in a short uniseriate series of cells; laminae anadromous, becoming catadromous towards the apex, herbaceous to firmly herbaceous, ovate to deltate, 2-to 3-pinnate, to 640 mm long, with up to 14 petiolated pinna pairs; rachises stramineous, adaxially shallowly sulcate, becoming narrowly winged towards the apex, eglandular or sparsely glandular, and moderately to sparsely set with scales and hairs, the scales stramineous to ferrugineous, chartaceous, sessile or short-stalked, narrowly lanceolate to filiform, to 8 x 1.5 mm, cuneate, the margins entire or denticulate, often with a few twisted filiform outgrowths, mostly from near the base, and glands (which may also occur on the scale laminae), the scale apex filiform, terminating in a short uniseriate series of cells; pinnae petiolate, the petiole to 20 mm long, the basal pinna pair inaequilaterally triangular to broadly ovate, or deltate, oblong-acuminate, ovate or lanceolate towards the lamina apex, to 320 mm long, to 250 mm wide, to 2-pinnate, the basal pair shorter or longer than the next pair above, subopposite to alternate, basally widely spaced, often somewhat imbricate higher up, with up to 10 petiolated pinnule pairs; pinna-rachises adaxially shallowly sulcate, the sulcus confluent with that of the rachis, pronounced abaxially, narrowly winged for most of the length, the wing proximally less conspicuous, eglandular or sparsely glandular, abaxially moderately to sparsely set with hairs and scales, the hairs and scales stramineous to ferrugineous, membranous to chartaceous, sessile or short-stalked, narrowly lanceolate-caudate to filiform, to 4 x 1 mm, cordate to narrowly cuneate, the margins entire, repand or denticulate, often with twisted filiform outgrowths, mostly from near the base, and glands (which often also occur on the scale laminae), the scale apex filiform, terminating in a uniseriate series of oblong cells; pinnules petiolate, the petiole to 5 mm long, aequilaterally to inaequilaterally narrowly triangular, to lanceolate, distally basiscopically decurrent, to 1-pinnate, the acroscopic pinnule on the basal pinnae to 94 mm long, to 34 mm wide, the basiscopic pinnule on the basal pinnae to 145 mm long, to 52 mm wide, widely spaced, often somewhat imbricate, with up to 2 pairs of petiolated segments; costae adaxially shallowly sulcate, often with a few glands and isocytic hairs, pronounced abaxially, narrowly winged, the wing continuous with that of the pinna-rachises, glandular or eglandular, variously set with isocytic or moniliform hairs and scales, the hairs often bear one or more glands near the base; segments spaced, inaequilaterally narrowly ovate-obtuse to oblong-obtuse, basiscopically decurrent, to 28 mm long, to 9 mm wide, shallowly to deeply lobed; lobes serrate, adaxially glabrous, with a few glands along and between the veins, and/or with a few filiform scales along the costa, abaxially with hairs and scales, the scales ferrugineous to stramineous, chartaceous, short-or long-stalked, narrowly lanceolate-caudate to filiform, to 3 x 1.2 mm, the margins entire to repand, often glandular, the scale apex terminates in a series of oblong cells, hairs uniseriate, often bearing one or more gland-like cells near the base, mostly occurring along the costa, and/or simple isocytic or moniliform hairs, occurring on the veins and lamina, and/or oblong to clavate glands (46-)95(-166) µm long, occurring on the costa, veins and/or lamina near the veins, or eglandular. Venation anadromous, becoming catadromous towards the lamina and pinna apex, pinnately branched in the segments, the veins branches pinnately branched, forked, or simple near the apex, evident, ending in the teeth near the margin, the endings slightly enlarged. Stomata of the anomo-and polocytic types, guard cells (30-)41(-62) µm long. Sori circular, to 1.6 mm in diameter at maturity, medial on the predominantly anadromous vein branches, discrete, essentially 2-seriate on the segments; sporangia stalk simple, with one or more glands, or with a long uniseriate hair, capsule with (9-)13(-21) indurated annulus cells, epistomium (3-)4(-6)-celled, hypostomium (3-)4(-8)-celled. Indusia persistent, brown, firmly herbaceous, reniform, to 1.6 mm in diameter, glabrous, the margin repand, rarely lacerate, often strongly revolute. Spores ellipsoidal, monolete, the perispore folded into low tubercules or reticulate ridges, finely rugose to ruminate, (28-)38(-50) x (20-) 25 (-31) µm.