Bolet sémillant ダイダイイグチ Crocinoboletus laetissimus
ダイダイイグチ Boletus laetissimus Hongo, Mem. Fac. Educ., Shiga Univ., Nat. Sci. 18: 49 (1968)
Diagnose princeps :
53) Boletus laetissimus Hongo sp. nov.
Pileo 4-8cm lato, e hemispherico ad convexum, sicco, subtomentoso vel subglabro, primitus laete aurantiaco (« cadmium orange ») vel « orange »), aetate ochraceo-aurantiaco (« zinc, orange », « ochraceous-orange » vel « yellow ocher »), tacto cyanescenti, margine primum incurvata; carne crassa, firma, aurantio-lutea, fracta cyanescenti, sapore miti, odore parum grato; tubulis depressis, 2.5-7 mm longis, aurantiacis, fractis +- cyanescentibus; poris rotundis, minutis, 2 -3 in uno mm, aurantio-igneis (« orange chrome »); stipite 5-7 cm longo, 3-17 mm crasso, subaequali vel subventricoso, velutino praecipue basi, pileo concolore, solido; sporis sub microscopio brunneomelleis, 9.5-12.5×4-5 µ, subfusoideis, laevibus; basidiis tetrasporis: cystidiis pororum 20-39 × 6.5-10 μ, fusoideis vel clavatis, tenui-tunicatis; tramate hymenophorali typi Boletorum.
Hab. : Gregarious on the ground in young oak forests (Quercus serrata), Tachiki-yama, Otsu-city, Sept. 6, 1966 (no.3306, Coll., M. Endo): Imodani, lshiyama-Nangô, Ôtsu-city, Sept. 1, 1966 (no. 3300); Sept. 3, 1966 (no. 3303); Oct. 5, 1966 (no. 3349- type); Sept.11, 1967 (no.3489),
Distr. : Endemic (Shiga).
Recognized by the brilliant orange colours and the blue staining of all parts when cut or bruised. The cuticle of the cap consists of interwoven filamentous yellow to orange yellow hyphae 5.5-8.5 µ wide. B. flavissimus (Murr.) Murr. is a similar, but bright golden yellow (« cadmium yellow » to « light cadmium ») species with the base of the stem inside and out deep carmine. B. pseudosulphureus Kalch, is also similar to B. laetissimus, but differs in the chrome yellow color and larger spores (11-18×5-7μ).
Polyene pigments from fruit-bodies of Boletus laetissimus and B. rufo-aureus (basidiomycetes).
Kahner L1, Dasenbrock J, Spiteller P, Steglich W, Marumoto R, Spiteller M.
Abstract
From fruit-bodies of the Japanese mushroom Boletus laetissimus two polyene pigments boletocrocin A and B were isolated and their structures determined by spectroscopic methods. The compounds represent diamides of hexadecaheptaenedioic acid with isoleucine and either aspartic acid or asparagine. The L-configuration of the amino acids was established after acid hydrolysis. The structures of five structurally related minor pigments were elucidated by LC-ESIMS.
Crocinoboletus is described as a new genus of Boletaceae to accommodate Boletus rufoaureus and B. laetissimus, characterized by its brilliant orange color of basidiomata caused by the presence of unusual boletocrocin polyene pigments, bluish olivaceous staining of all parts when bruised, smooth basidiospores, and the pileipellis which has an interwoven trichoderm at the middle part of the pileus and a cutis at the margin of the pileus. Prior molecular phylogenetic analyses also confirmed the two taxa are not members of the genus Boletus s.s., but form a well-supported generic lineage within Boletaceae. Consequently a description, color photos of fresh basidiomata, line-drawings of microstructures and a comparison of Crocinoboletus with allied taxa are presented.