Leptopteris superba (Colenso) C.Presl

Rhizomes erect, short or sometimes forming woody trunks up to 1000 mm tall. Fronds 250–1000 mm long. Stipes 15–190 mm long, pale brown, woolly hairy. Laminae 2-pinnate-pinnatifid, elliptic, 160–980 mm long, 60–250 mm wide, dark green, membranous and translucent, densely woolly hairy especially on costae of primary and secondary pinnae. Primary pinnae in 30–60 pairs, narrowly ovate to linear, with acute apices, crowded along rachis; the longest at or about the middle of the rachis, 30–130 mm long, 6–23 mm wide; the basal pair 1–20 mm long. Secondary pinnae oblong or narrowly elliptic, 6–11 mm long, 3–5 mm wide, sessile, divided most of the way to the midrib. Ultimate laminal segments linear, obtuse, bent upwards at 90° to plane of frond. Sporangia scattered on abaxial surfaces, confined to proximal part of primary and secondary pinnae.

Leptopteris superba has very thin, membranous fronds, resembling filmy ferns, and can be confused with them when very young. It is distinguished from L. hymenophylloides by its shorter stipe, lamina that tapers to both ends, shorter and narrower pinnae, and by its ultimate laminal segments that are bent upwards away from the lamina surface like the pile of a carpet. The basal pinnae (1–20 mm long) are significantly shorter than those in L. hymenophylloides (50–120 mm long) and this character alone will usually distinguish the two species.

A terrestrial fern that occurs in lowland to montane forest, growing best in cool, shaded forest in wetter sites and valley floors, sometimes in boggy ground. It requires constant high humidity, and cannot tolerate high temperature or light intensity. It is found primarily in beech, podocarp or kāmahi forest, extending locally into subalpine scrub.

Leptopteris superba and L. hymenophylloides frequently occur together in wet, forested areas, and they hybridise readily. Hybrids (Leptopteris ×intermedia) show regular bivalent formation at meiosis and have spores of normal appearance, but there is no evidence for second-generation hybrids (Brownsey 1981).

n = 22 (Manton 1950; Brownlie 1958; Brownsey 1981).