Synonymy:
Eccilia undata (Gillet) Quél., Bull. Soc. Amis Sci. Nat. Rouen, Sér. II 15: 157 (1880) [1879]
Rhodophyllus undatus (Gillet) Quél., Enchiridion Fungorum in Europa media et praesertim in Gallia Vigentium: 62 (1886)
Orcella undata (Gillet) Kuntze, Revis. gen. pl. (Leipzig) 2: 863 (1891)
Hyporrhodius undatus (Gillet) Henn., in Engler & Prantl, Nat. Pflanzenfam. (Leipzig) 1(1**): 257 (1898)
Paxillus undatus (Gillet) Ricken, Die Blätterpilze: 95 (1911)

Agaricus undatus Fr., Epicrisis Systematis Mycologici: 149 (1838) [1836-1838]
Clitopilus undatus Gillet, Les Hyménomycètes ou Description de tous les Champignons (Fungi) qui Croissent en France avec l'indication de leurs propriétés utiles ou vénéneuses (Alençon): 407 (1876) [1878]
Eccilia sericeonitida P.D. Orton, Trans. Br. mycol. Soc. 43(2): 175 (1960)

Agaricus undatus var. viarum Fr., Hymenomyc. eur. (Upsaliae): 199 (1874)
Clitopilus undatus subsp. viarum (Fr.) Sacc., Syll. Fung. (Abellini) 5: 702 (1887)
Clitopilus viarum (Fr.) Mussat, in Saccardo, Syll. Fung. (Abellini) 15: 94 (1901)
Rhodophyllus undatus var. viarum (Fr.) Romagn., in Kühner & Romagnesi, Fl. Analyt. Champ. Supér. (Paris): 183 (1953)
Entoloma undatum var. viarum (Fr.) Courtec., Transect Mycologique Dunaire sur la Cote d'Opale (France). Les Groupements Heliophiles et Arbustifs de la Xerosere. These Universite de Lille 11; Faculte de Pharmacie: 50 (1983)
Entoloma undatum var. viarum (Fr.) Courtec., in Courtecuisse, Priou & Boisselet, Docums Mycol. 16(no. 62): 11 (1986)

Eccilia undata var. ombrophila Singer, Collect. Botan. 1(3): 219 (1947)

Rhodophyllus undatus var. odorus J. Favre, Beitr. Kryptfl. Schweiz 10(no. 3): 212 (1948)

Rhodophyllus sericeonitidus (P.D. Orton) M.M. Moser, Kl. Krypt.-Fl. Mitteleuropa - Die Blätter- und Bauchpilze (Agaricales und Gastromycetes) (Stuttgart) 2b/2: [1] (1967)
Entoloma sericeonitidum (P.D. Orton) Arnolds, Biblthca Mycol. 90: 350 (1982)
Claudopus sericeonitidus (P.D. Orton) P.D. Orton, Mycologist 5(3): 126 (1991)
Paraeccilia sericeonitida (P.D. Orton) Largent, Entolomatoid fungi of the Western United States and Alaska (Eureka): 378 (1994)

Entoloma undatum f. longipes Noordel., Annls Univ. turku., Ser. A II (Rep. Kevo subarct. Res. Stn 17) 66: 39 (1981)

Paraeccilia sericeonitida var. ligniphila Largent, Entolomatoid fungi of the Western United States and Alaska (Eureka): 380 (1994)

Entoloma undatum var. aciesterilis Vila & Llimona, Revta Catal. Micol. 31: 107 (2009)

Position in classification:
Entoloma, Entolomataceae, Agaricales, Agaricomycetidae, Agaricomycetes, Basidiomycota, Fungi

Note:
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