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''Sutorius eximius'', commonly known as the lilac-brown bolete, is a species of fungus in the family Boletaceae. This bolete produces fruit bodies that are dark purple to chocolate brown in color with a smooth cap, a finely scaly stipe, and a reddish-brown spore print. The tiny pores on the cap underside are chocolate to violet brown. It is widely distributed, having been recorded on North America, South America, and Asia, where it grows in a mycorrhizal relationship with both coniferous and deciduous trees. Originally described in 1874 as a species of ''Boletus'', the fungus has also been classified in the genus ''Leccinum'' because of the scabers on the stipe, or in ''Tylopilus'' because of the color of the spore print. Molecular genetic analysis revealed that the lilac-brown bolete was separate from both of these genera, and merited placement in a new genus. ''Sutorius'' was created to contain this bolete and the closely related Australian species ''S. australiensis''. Although the lilac-brown bolete was once considered edible, caution is typically recommended in modern field guides when considering this bolete for the table after several poisonings were reported in northeastern North America. Symptoms include severe gastrointestinal distress with vomiting, diarrhea, and nausea that generally lasts less than 24 hours. ==Taxonomy== The species was originally described as ''Boletus robustus'' by American mycologist Charles Christopher Frost in 1874, from specimens collected in Vermont. He noted that the cap was "chocolate color, fleshy, and so succulent that it is difficult to dry and preserve".〔 The name assigned by Frost, however, is an illegitimate homonym of a name previously used for a different species by Miles Joseph Berkeley in 1851.〔 Charles Horton Peck published the new name ''Boletus eximius'' for the same species in 1887.〔 William Alphonso Murrill transferred the species to ''Ceriomyces'' in 1909,〔 but this genus is no longer recognized, having largely been subsumed into ''Boletus''.〔 Various authorities have treated the taxon as either a ''Boletus'', ''Leccinum'', or ''Tylopilus'', depending on which morphological characteristics they deemed most significant.〔 Rolf Singer initially considered the species most appropriately placed in ''Tylopilus'' on account of the reddish-brown spore print,〔 a taxonomic opinion shared by Alexander H. Smith and Harry Thiers, who wrote "Concerning whether or not the species should be placed in ''Leccinum'', we can only say that the color of the stipe ornamentation is merely a reflection of the color of the stipe generally and that it does not change color in a characteristic pattern as it ages. For this reason we exclude it from ''Leccinum'' and agree with Singer that it is a ''Tylopilus''."〔 Later however, Singer thought the somewhat scabrous ornamentation of the stipe justified a placement in ''Leccinum''.〔 René Pomerleau had previously (1959) placed the species in ''Leccinum'',〔 but this transfer was invalid, as no basionym was specified.〔 Roy E. Halling designated a lectotype specimen in 1983 from Frost's original collections.〔 Early molecular evidence suggested that the lilac-brown bolete was genetically distinct from the genera in which it had formerly been placed.〔 In 2012, Halling and colleagues published molecular evidence indicating that the species did not belong in either ''Tylopilus'' or ''Leccinum'' as it does not share a recent common ancestor with either of those genera. Recognizing its genetic and morphological distinctiveness, they created the genus ''Sutorius'', with ''S. eximius'' as the type species.〔 As of 2015, the only other species in ''Sutorius'' is ''S. australiensis'', found in Australia. The generic name ''Sutorius'' is derived for the Latin word for "cobbler" (''sutor''), referring to Charles Frost's profession.〔 The epithet ''eximius'' means "distinguished" or "excellent in size and beauty".〔 Although Frost's reason for using this name is not known with certainty, Peter Roberts and Shelley Evans speculate "Perhaps it was the violet-brown colors, which are quite attractive in a formal, nineteenth-century manner."〔 ''S. eximius'' is commonly known as the "lilac-brown bolete".〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Sutorius eximius」の詳細全文を読む スポンサード リンク
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