20. Diplazium polypodioides Blume (1828: 194). Fig. 26. Type: INDONESIA. Java, Blume s.n. (lectotype L0051563!; designated by Hovenkamp, 2019: 63). Plants terrestrial. Stems massive, erect, 7–8 cm diameter, apex densely scaly; scales 14–20 by 1.0– 1.5 mm, linear long tail apex, dark brown to nearly black, margin thick, toothed. Fronds up to 1.70 m, bipinnaate; petioles up to 1 m, 1.0– 1.5 cm diameter, brown, surface prickly due to scars of fallen scales, densely scaly near base. Laminae up to 1.0 × 0.7 m, ovate-deltoid in outline, glabrous, papyraceous, light green; lower pinnae 55–60 × 25–30 cm, alternate, oblong in outline, apex acuminate, stalked, stalks 4–5 cm; pinnules 10–12 × 3–4 cm, subopposite, oblong, apex acuminate base subtruncate, margin lobed, lobe deep close to costule, about 10 × 5 mm, oblong, oblique, apex round or obtuse, sharply serrate at margin, stalked, stalks 2–3 mm; veins pinnate, about 10 pairs, free or forked. Sori 2–3 mm, along veinlets, close to costule, indusiate; indusia linear, thin, persistance. Spores monolete, 37.5–45.0 × 22.5–25.0 μm, bilateral, concavo-convex to plano-convex, perispore present; ornamentation: prominent wing folds. Thailand: —NORTHERN: Chiang Rai (Mae Lao), Chiang Mai (Doi Suthep, Mae Klang, Doi Inthanon), Phrae (Mae Sai), Tak, Phitsanulok (Phu Miang); SOUTH-WESTERN: Kanchanaburi, Phetchaburi; SOUTH-EASTERN: Chantaburi (Khao Soi Dao). PENINSULAR: Surat Thani (Ban Don), Ranong (Phato), Nakhon Si Thammarat (Khao Luang). Distribution: — Sri Lanka, India, Buhtan, China, Japan, Taiwan Island, Cambodia, Vietnam, Laos, Myanmar, Malaysia, Indonesia and Papua New Guinea. Ecology: —On humus-rich mountain slopes in high humidity areas at 500–1,200 m elev. Throughout the country, usually at edge of forests or in clearing, not in deep shade. Specimens Examined:— THAILAND. Chumphon, Lanng Suan, A.F. G. Kerr 12158 (BK); Chiang Mai, Mae Dang, J.F. Maxwell 90-34 (L); Chiang Rai, Ban Saen Sa-at, K. Bunchuai & B. Nimanong 1421 (L); Nakhon Si Thammarat, Khao Luang, M. Tagawa, K. Iwatsuki & N. Fukuoka T5269 (L); Phetchaburi, Kaeng Krachan, M.F. Newman, T. Boonthavikoon, C. Hemrat & D.J. Middleton 1095 (L); Nan, Doi Phuka, P. Pongkai 8 (BCU); Chiang Rai, Khunkorn waterfalls, P. Ratchata 12 (BCU); Chiang Rai, Mae Swai, Pragad 916 (BK); Chiang Mai, Doi Suthep, S. Mitsuta T50237 (QBG); Ratchaburi, Suan Phueng, Suan Phueng Trip 79 (BCU); ibis., Suan Phueng Trip 81 (BCU); Kanchanaburi, si yok, T. Vougthavone 153 (BK, BKF) Prachuap Khiri Khan, Huaiyang waterfalls, Y. Yuyen 191 (BCU). BHUTAN. B. Barhtolomew et al. 3768 (PE). INDIA. Darjiling, C.B. Clarke 35382 (K); ibis., C.B. Clarke 8646 (K); Ponmudi, K.U. Kramer 6197 (K); Sikkim, T.C. Jerdon 12 (K); Idukki, V.S. Manickam RHT3218 (K). INDONESIA. Borneo, M.S. Clemens 40806 (BM); Java, PE-BO Team 18 (PE); Tahura, W. R. Yu 18 (PE). JAPAN. Dalhousie, F.E.W. Venning 502 (PE); no Locality, M. Tagawa 2864 (PE). MYANMAR. Tuang, Nan Tamwi Tuang, J.F. Maxwell 75-281 (BK). NEPAL. Mai valley, J.D. Hooker s.n. (K). SRI LANKA. Central Province, C. V. 1352 (K); no Locality, Perad 1352 (B); ibis., W. Robinson 81 (K). VIETNAM. Ha Giang, D. K. harder et al. 5382 (PE).

Published as part of Pongkai, Puttamon, Zhang, Li-Bing, Boonkerd, Thaweesakdi & Pollawatn, Rossarin, 2023, Revision of the fern genus Diplazium (Polypodiales: Athyriaceae) in Thailand, pp. 1-69 in Phytotaxa 631 (1) on pages 46-48, DOI: 10.11646/phytotaxa.631.1.1, http://zenodo.org/record/10422862