Blechnum ambiguum
Fertile pinnae c. one third to a half of the width of the sterile pinnae. Rhizome with non-fleshy, circinnate buds. Scales of the rhizome light fawn or brown or ferruginous, sometimes slightly darker towards the centre when old, dull to slightly glossy, narrowly lanceolate to narrowly ovate. Spores with a reticulate perispore, 49–75µm X 44-56µm; the wings 3.75–11µm diam, surrounding the spore. Pinnae light to medium green, dull, slightly auriculate at the base. Widespread. Common. RF and tall open forests. Ss, usually on rock ledges under caves or near waterfalls or on wet cliff-faces