Dicranopteris linearis

Dicranopteris linearis (Burm.f.) Underw.

Family     : Gleicheniaceae

Plants terrestrial or epilithic. Rhizome rooting at irregular intervals, wide-creeping, irregularly branched, corneous, castaneous, to 3 mm in diameter, initially moderately set with stellate hairs, glabrous later, hairs crustaceous, castaneous, sessile or short-stalked, rays uni- or pluricellular, often branched, uniseriate, apical cell of the terminal ray acicular or narrowly obovate and thin-walled, to 2.8 mm long. Fronds spaced, to 105 mm apart, erect or scandent, with indeterminate growth; stipe firm, yellow to brown, stramineous higher up, terete, to 1.1 m long, to 5 mm in diameter, initially closely set with hairs, hairs chartaceous to thinly crustaceous, castaneous, sessile, rays uni- or pluricellular, uniseriate, terminal ray much longer than the rest, of which the apical cell may be acicular or narrowly obovate, to 4 mm long; lamina pinnately branched, with one or more consecutive storeys of consecutive pinna pairs arising from each side of the terminal rachis bud, each bifurcation also flanked by a pair of accessory branches; rachis yellow, brown or stramineous, terete, to 4.2 mm in diameter, initially closely set with scales similar to those on the stipe, also with smaller hairs at the point where the pinnae branch from the rachis, hairs short-stalked, stellate, rays simple or branched, straight or twisted, to 1 mm long; pinnae reniform to transversely broadly elliptic in outline, to 3 times pseudo-dichotomously branched, with a dormant bud in the axil of each bifurcation, pinna-rachis branches terete or adaxially slightly flattened, initially moderately scaled, glabrous later, scales stramineous, stellate, to 1.8 mm long; ultimate branches adaxially convex, pectinately pinnatifid, inequilaterally narrowly lanceolate to linear-acuminate, to 220 mm long, to 40 mm wide, basal acroscopic segments shorter than those higher up, basal basiscopic segment enlarged; rachis and dormant buds densely set with crustaceous, ferrugineous to castaneous, stellate hairs similar to those on the rhizome, each bud subtended by a pair of simple or lobed pseudo-stipules; accessory branch pairs flank each pinna pair and consecutive pinna pseudo-dichotomies, adaxially shallowly sulcate, sessile, pectinately pinnatifid, narrowly lanceolate, to 180 mm long, to 43 mm wide; segments firmly herbaceous, linear-acuminate to linear-obtuse, entire, emarginate, to 20 mm long, to 4 mm wide, glabrous adaxially, abaxially with ferrugineous, stellate scales along the costa and with 2-celled hairs along the veins. Venation catadromous, pinnately forked, ending in the margin. Sori superficial, inframedial on acroscopic vein branches, with 8-15 sporangia per sorus, exindusiate. Sporangium short-stalked, multiseriate, annulus oblique, complete. Spores yellow, numerous, tetrahedral, trilete, with prolonged angles, rugulose, foveolate, to 45 µm in equatorial diameter.