Blechnum hieronymi Brause

Rhizome sometimes epiphytic and scandent, erect, 0.4-2.5 cm thick, clothed with narrowly elliptic to subdeltoid, acuminate, entire, reddish, brown or black scales, some­times with paler margins, to 1.9 by 0.4 cm; slender creeping rhizomes give rise to a succession of single fronds. Fronds dimorphic, both sterile and fertile fronds either clustered (or remote if rhizome scandent), 13-45(-130) by 10-20 cm; fertile fronds with little or no photosynthetic surface. Stipes 11-20(-70) cm (fertile usually longer), 0.3-0.4 cm diam., reddish brown, dark purplish to purplish black near base and on abaxial surface, scales dense, at base similar in size and colour to those of the rhizome, but towards the rhachis smaller lighter stramineous or ginger-brown scales some with a dark central spot and with cordate appressed bases, often mixed with linear twisted hairs and hair-like scales. Lamina oblong-narrowly elliptic, abruptly truncate at the base, (11-)14-38 pairs of pinnae; sterile lamina 14-50 by 16 cm; fertile lamina up to 45 by 15 cm. Rhachis and costae yellowish brown, with varying amount of purple pigmentation on abaxial side of rhachis, scales sparse, deciduous, similar to those of the stipe but smaller and paler or sometimes with dark central spot. Sterile pinnae coriaceous, glabrous, in fresh material, olive green on the adaxial surface, paler on the abaxial face; margins slightly revolute and varying from entire to finely serrate and dentate at the apices, narrowly elliptic or linear-narrowly elliptic to oblong, sometimes tending to become slightly falcate towards the apex of the lamina, acuminate or acute at apices, rounded at their bases, 6-10(-14) by 0.75-1.7(-2.2) cm, adnate towards apex of lamina, otherwise sessile, shortly or distinctly petiolate, alternate or subopposite, 0.8-2 cm between the costae, most distant distal and mid-region pinnae at an angle of 45° or more to the rhachis, veins slender, thickened at their apices, single or once furcate, sub remote, terminating in an ovoid gland, basal pinnae not or only slightly reduced, more distant, terminal pinna significantly larger than subterminal pinnae, sometimes similar in size to those of the largest mid-frond region. Pinnae on small fronds, especially those produced from a slender creeping rhizome, tend to be short ovate or rounded, with wavy margins giving a dentate appearance. Fertile pinnae linear acuminate or mucronate, not revolute at maturity, 7.5-12 by 0.2-0.5 cm, 0.8-3.3 cm distant (between costae at rhachis), upper pinnae shorter, adnate, shortly de­current, lower ones shortly petiolate, sori occupying the whole face except for a short sterile apical zone, 0.1-0.6 cm long. Spores 72.2 by 54.5 µm (from 17 herbarium specimens), perine alate to costate-alate and loosely reticulate, lacunae large irregular polygons, wing-like muri with ciliate margins, scabrous, microreticulate or rugulose between muri, exine smooth, scabrous or microverrucose.