Asplenium zanzibaricum Baker
Aspidium sulcinervium Hieron.
Dryopteris sulcinervia (Hieron.) C.Chr.
Diplazium sulcinervium (Hieron.) C.Chr.
Cornopteris sulcinervia (Hieron.) Tardieu

Rhizome erect, with a short caudex up to 0.4-1.2m × 15 cm; rhizome scales linear-lanceolate in outline, finely attenuate, margins entire, with numerous stiff spiniform trichomes, very narrowly striate with raised walls of the elongate reticulation, 1.5–3.2 cm x 0.5–1.5(–2) mm, dark brown. Fronds monomorphic, tufted, arching, 1-2.5m tall, firmly herbaceous. Stipe up to 1.5 m long, pale brown, smooth except for a numerous scales similar to rhizome scales near the base. Lamina 3-pinnatifid to 3-pinnate, ovate-lanceolate to broadly ovate in outline, 1.3–1.6 x 0.9–1.1 m, with about 15 pairs of pinnae; pinnae up to 70 x 25 cm, stalk up to 2.5 cm long with 12 to 27 pairs of pinnules; pinnules ovate-lanceolate to to oblong-triangular, apex pointed, base shortly petiolate, truncate to cordate, up to 13 x 4 cm, cut to the costules into 13-15 pairs of lobes; lobes oblong in outline, slightly falcate with rounded apices, margins serrate, op to 2 x 0.8 cm, glabrous on both surfaces, but costae and costules with scattered, minute scales; veins free; rhachis pale brown, subglabrous. Sori up to 23 per pinnule lobe, oblong to linear-oval, 0.7-3 mm long, often acroscopic sori arranged back to back; indusium erose.

Could be confused with D. nemorale which differs in having longer and fewer sori per lobe and a smooth stipe base.

zanzibaricum: of Zanzibar, where this fern was first collected.

Deeply shaded streambanks in wet evergreen forest, often where there is a break in the canopy thus allowing slightly more light, bamboo forest, occasionally in swampy areas.

Africa, Madagascar, Comoro islands.

Cameroon, Dem. Republic of Congo, Guinea, Kenya, Liberia, Malawi, Mozambique, Rwanda, South Africa, Tanzania , Uganda, Zambia, Zimbabwe.

Terrestrial.