Synoptic Revision of Diplazium (Athyriaceae) in Rwanda with description of Diplazium cyamudongoense sp. nov. Author Fischer, Eberhard 0000-0001-7455-9833 Institute for Integrated Natural Sciences-Biology, University of Koblenz, Universitätsstrasse 1, 56070 Koblenz, Germany. efischer @ uni-koblenz. de; https: // orcid. org / 0000 - 0001 - 7455 - 9833 efischer@uni-koblenz.de Author Lobin, Wolfram Botanical Gardens Bonn University, Meckenheimer Allee 171, D- 51115 Bonn, Germany. text Phytotaxa 2023 2023-06-26 600 3 169 183 http://dx.doi.org/10.11646/phytotaxa.600.3.4 journal article 54702 10.11646/phytotaxa.600.3.4 2a1cbd1e-993f-4c7c-b5ed-abe41c0fe91e 1179-3163 8080860 Diplazium humbertii (C.Chr.) Pichi Sermolli (1973: 444) ( Figs. 4 E–F , 6–7 ). Athyrium humbertii Christensen (1937: 54) Lectotype (designated by Pichi Sermolli 1973 ):— D.R. CONGO . North Kivu : Montagnes à l’Ouest du Lac Kivu (Congo Belge). Forêt, 2000–2400 m , February–March 1929 , H. Humbert 7497 ( BM000918405! ; isolectotype BM000918404! ) Specimens seen:RWANDA . Western Province: Nyungwe National Park, route Astrida (= Huye) – Bukavu, vers km 93, forêt de Rugege (= Nyungwe) près d’Uwinka, Territ. Shangugu (= Rusizi), 24 September 1956 , G. Troupin 2598 (BR0000013688578); a sud-est del lago Kivu a 45 km da Bukavu lungo la strada per Astrida (= Huye), 15 August 1956 , R. Pichi Sermolli 5323 (BR0000013688585); Forêt de Nyungwe, environs de Kamiranzovu, Préfecture Cyangugu (= Rusizi), September 1971 , G. Bouxin 1211 (BR0000013688462); Kamiranzovu, 11 August 2007 , E. Fischer s.n. (KOBL); Cyamudongo Forest, 4 April 2021 , E. Fischer s.n. (KOBL). Distribution in Rwanda : —Western Province, Nyungwe National Park. Distribution in Africa: Eastern D.R. Congo , Western Uganda , Western Rwanda , Western Burundi , Western Tanzania . Albertine Rift endemic. Habitat: —Montane rainforest, elev. 1900–2400 m . Note: —The spores ( Fig. 4 E, F ) resemble those of Diplazium cyamudongoense sp. nov. (Fig, 4 A–D) and have a cristate perispore, 54.3–57.2 × 28.6–37.1 µm, the alae are 5.7–7.15 µm high and 1.5–2.86 µm wide. The remaining perispore bears up to 1.4–1.6 µm long spine-like scattered projections.