Alsophila thomsonii (Bak.) R. M. Tryon

thomsonii: first collected by J. Thomson (1858-1895), a British plant collector

Tree fern. Caudex slender, 2.5 m × 15 cm, the top carrying thinly coriaceous fronds. Stem without spines and without aphlebia. Stipe glossy brown, set with dark brown scales towards the base, scales up to 20 mm long, lanceolate, margins pale, lacerate. Lamina up to 2m × 0.8m, 2-pinnate to 3-pinnatifid, elliptic in outline. Pinnae narrowly oblong-attenuate, deeply to shallowly pinnatifid; pinnule lobes from almost semicircular to oblong, slightly falcate, apex rounded to acute, undersurface with sparce stiff twisted hairs along the costules; rhachis pale brown with twisted hairs when young, becoming hairless at maturity. Sori round, set in 2 rows along each side of the costules, indusium cup-shaped fragmenting with maturity.

Angola, Burundi, DRC, Malawi, Mozambique, Tanzania, Zambia, Zimbabwe