Synonymy:
Boletus ferrugineus Schaeff., Fung. bavar. palat. nasc. (Ratisbonae) 4: 85 (1774)
Xerocomus subtomentosus var. ferrugineus (Schaeff.) Krieglst., Beitr. Kenntn. Pilze Mitteleur. 7: 77 (1991)

Boletus spadiceus Schaeff. ex Fr., Epicrisis Systematis Mycologici: 415 (1838) [1836-1838]
Boletus subtomentosus var. spadiceus (Schaeff. ex Fr.) Cooke & Quél., Clavis syn. Hymen. Europ. (London): 164 (1878)
Versipellis spadicea (Schaeff. ex Fr.) Quél., Enchiridion Fungorum in Europa media et praesertim in Gallia Vigentium: 158 (1886)
Xerocomus spadiceus (Schaeff. ex Fr.) Quél., Fl. mycol. France (Paris): 417 (1888)
Suillus spadiceus (Schaeff. ex Fr.) Kuntze, Revis. gen. pl. (Leipzig) 3(3): 536 (1898)

Boletus spadiceus Krombh., Naturgetr. Abbild. Beschr. Schwämme (Prague) 10: tab. 36, fig. 12-18 (1846)

Boletus variicolor Berk. & Broome [as 'variecolor'], Ann. Mag. nat. Hist., Ser. 3 15: 318 (1865)
Suillus variicolor (Berk. & Broome) Kuntze, Revis. gen. pl. (Leipzig) 3(3): 536 (1898)
Xerocomus subtomentosus var. variicolor (Berk. & Broome) H. Engel & E. Ludw. [as 'variecolor'], in Engel, Dermek, Klofac, Ludwig & Brückner, Schmier- und Filzröhrlinge s.l. in Europa, Die Gattungen Boletellus, Boletinus, Phylloporus, Suillus, Xerocomus (Weidhausen b. Coburg): 192 (1996)
Xerocomus ferrugineus f. variicolor (Berk. & Broome) Klofac [as 'variecolor'], Österr. Z. Pilzk. 16: 258 (2007)

Boletus citrinovirens Watling, Notes R. bot. Gdn Edinb. 29(2): 266 (1969)

Boletus spadiceus var. gracilis A.H. Sm. & Thiers, Boletes of Michigan (Ann Arbor): 254 (1971)
Xerocomus spadiceus var. gracilis (A.H. Sm. & Thiers) L.D. Gómez, Revta Biol. trop. 44(Suppl. 4): 64 (1997) [1996]

Boletus spadiceus var. rufobrunneus Thiers, California Mushrooms (New York): 92 (1975)

Boletus spadiceus var. furcatus T.J. Baroni, Largent & Thiers, Mycologia 68(3): 659 (1976)

Xerocomus ferrugineus f. aurantiiporus Klofac & Krisai, Österr. Z. Pilzk. 28: 10 (2020)

Position in classification:
Xerocomus, Boletaceae, Boletales, Agaricomycetidae, Agaricomycetes, Basidiomycota, Fungi

Note:
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