Sutorius Halling, Nuhn & N.A. Fechner, in Halling et al., Mycologia 104(4): 955 (2012)
Etymology: sutor (-ius) = Latin (m.) for cobbler; specifically Charles C. Frost, a Vermont shoemaker, who described the species Boletus robustus non Fr.
Diagnosis: This genus differs from all other genera of Boletaceae in its different color of hymenophoral tubes and pores; all parts of basidioma often staining blue to dark blue immediately, rarely unchanging when cut or touched; rarely reticulate but pruinose-furfuraceous stipe; trichodermium pileipellis and smooth basidiospores.
Basidioma stipitate-pileate, sometimes sequestrate. When basidioma stipitate-pileate; Pileus hemispherical, convex or applanate, subtomentose to tomentose, sometimes glabrous, dry, staining blue, rarely unchanging when touched, sometimes margin slightly appendiculate; context cream-yellow to light yellow, sometimes white to pallid, always staining blue immediately, or sometimes unchanging when injured. Hymenophore adnate, adnexed, sinuate to free; hymenophoral surface brown, dark brown, reddish brown, sometimes grayish white when young, and becoming yellowish brown, sometimes purplish pink, brownish pink to purplish red or dark purplish when mature, staining blue to dark blue immediately, or sometimes unchanging when injured; pores angular, nearly round to round; tubes yellow to bright yellow, sometimes grayish white when young, becoming ochraceous to olive, or sometimes becoming purplish pink, brownish pink to purplish red or dark purplish when mature, always staining blue to dark blue immediately, or sometimes unchanging when injured. Stipe central, covered with finely pruinose-furfuraceous scales but usually without reticulations, staining blue, or sometimes unchanging when touched; context staining blue immediately, or sometimes unchanging when injured; basal mycelium white to cream yellow or brown. Basidiospores smooth, subfusiform, brownish yellow. Pleuro- and cheilocystidia subfusiform-ventricose or sometimes clavate. Pileipellis an interwoven trichodermium. When basidioma sequestrate, gleba loculate, always exposed, and context yellow, always staining blue immediately when bruised. Basidiospores yellow–brown, brown to cinnamon brown. Clamp connections absent.
Index Fungorum number: IF563942
Notes: Sutorius was described in details by Halling et al. (2012). Not long after, the name Neoboletus Gelardi et al. (2014) was introduced for a clade closely related to it, which was labeled as ‘‘Clade 37’’ in Wu et al. (2014). The genus Neoboletus was temporarily accepted in an earlier paper by Wu et al. (2016). However, after incorporating additional species, this clade was collapsed into Sutorius, and the members of Neoboletus were not clustered within a highly-supported clade. Morphologically, the pileipellis structures of these two groups are similar to each other, both of which can be regarded as trichodermium; the stipe surface of those species are all covered with pruinose-furfuraceous squamules; and the surfaces of the hymenophores are all dark in color. Taken the above mentioned facts and the guidelines of Vellinga et al. (2015) into consideration, we decided to treat Neoboletus as a synonym of Sutorius here.
Type species: Sutorius eximius (Peck) Halling, M. Nuhn & Osmundson 2012, in Halling et al., Mycologia 104(4): 955 (2012)
Sutorius australiensis (Bougher & Thiers) Halling & N.A. Fechner 2012
Sutorius brunneissimus (W.F. Chiu) G. Wu & Zhu L. Yang 2016
Sutorius eximius (Peck) Halling, M. Nuhn & Osmundson 2012
Sutorius junquilleus (Quél.) G. Wu & Zhu L. Yang 2016
Sutorius magnificus (W.F. Chiu) G. Wu & Zhu L. Yang 2016
Sutorius subrufus N.K. Zeng, H. Chai & S. Jiang 2019
Sutorius thibetanus (Shu R. Wang & Yu Li) G. Wu & Zhu L. Yang 2016
Sutorius venenatus (Nagas.) G. Wu & Zhu L. Yang 2016
Halling RE, Nuhn M, Fechner NA, Osmundson TW, Soytong K, Arora D, Hibbett DS (April 11, 2012). "Sutorius: a new genus for Boletus eximius". Mycologia. 104: 951–61. doi:10.3852/11-376
Wu G, Li YC, Zhu XT, Zhao K, Han LH, Cui YY, Li F, Xu JP, Yang ZL. 2016. One hundred noteworthy boletes from China. Fungal Diversity. 81:25-188