Allantodia similis W. M. Chu, Acta Bot. Yunnan. 3: 337. 1981.
Plants evergreen, large. Rhizome ascending, apex with adpressed scales; scales brown, broadly lanceolate, membranous, margin toothed and inconspicuously black; fronds approximate to distant. Fertile frond up to 2 m; stipe black-brown at base, upward pale green, shorter than lamina, base up to 7 mm in diam., with slightly fleshy, green, shortly aculeate or verrucose protuberances throughout stipe, or at lower part of stipe; lamina 2-pinnate with pinnules pinnatilobate, ovate-deltoid, up to 1 m × 80 cm, apex acuminate; pinnae up to 12 pairs, alternate, slightly ascending, 1-pinnate, acuminate at apex; lower pinnae broadly oblong-lanceolate, with stalk up to 10 cm, basal pinnae slightly shortened, second basal pinnae largest, up to 70 × 30 cm; pinnules up to ca. 13 pairs, alternate or subopposite, spreading, lanceolate, broadly lanceolate, or broadly deltoid-lanceolate, symmetrical or nearly symmetrical, up to 10(-15) × 2-3(-5) cm, base truncate or broadly cuneate, sometimes slightly cordate, pinnatilobate to pinnatipartite, apex acuminate or shortly caudate; lower pinnules shortly stalked, upper pinnules sessile; pinnule lobes contiguous, nearly symmetrical, spreading, oblong or rectangular, apex rounded or truncate, rarely acute, entire or shallowly serrate; veins visible abaxially, not prominent adaxially, veinlets up to 11 pairs per lobe, ascending, simple or rarely forked. Lamina thinly papery when mature, green, dark adaxially, costules with granular thin glands adaxially, abaxially minutely scaly; rachis and costae abaxially sometimes with fleshy, green, small verrucose or shortly aculeate protuberances. Sori linear, membranous, entire; spores reniform, perispore hyaline and wide, not rugate, tuberculate. n = 41*.
Tropical rain forests, beside streamlets; 300-1200 m. Yunnan.
Diplazium simile is similar to D. maximum in the lamina shape but differs by the rhizome ascending to erect; scales sparse, adpressed, brown, not shiny, with inconspicuously black margin; stipe and rachis with ± green, fleshy, verrucose or shortly aculeate protuberances; costa and costule with granular thin glands; and spores with prominent wide perispore.
In some plants, the lamina is 1-pinnate, ca. 50 × 30 cm; and the pinnae are lanceolate, pinnatifid to pinnatipartite.