Ischnoderma benzoinum
Ischnoderma benzoinum
The bracket benzoin (Ischnoderma benzoinum (Wahlenb.) P. Karst., 1881) is a mushroom belonging to the Fomitopsidaceae family.
Systematic –
From a systematic point of view it belongs to:
Eukaryota domain,
Fungi Kingdom,
Division Basidiomycota,
Subdivision Agarcmonycotina,
Class Agaricomycetes,
Subclass Incertae sedis,
Order Polyporales,
Family Fomitopsidaceae,
Genus Ischnoderma,
Species I. benzoinum.
The terms are synonymous:
– Boletus benzoinus Wahlenb.;
– Boletus rubiginosus Schrad.;
– Boletus velutinus Schumach.;
– Boletus velutinus Vahl;
– Ganoderma rubiginosa (Fr.) Bres.;
– Ischnoderma resinosum f. benzoinum (Wahlenb.) Pilát;
– Lasiochlaena benzoina (Wahlenb.) Pouzar;
– Polyporus benzoinus (Wahlenb.) Fr.;
– Polyporus benzoinus Wahlenb.;
– Polyporus benzoinus var. morosus (Kalchbr.) Cooke;
– Polyporus guttatus Weinm.;
– Polyporus morosus Kalchbr.;
– Polyporus nigrorugosa Lloyd;
– Polyporus pini-silvestris Allesch.;
– Polyporus resinosus subsp. benzoinus (Wahlenb.) P.Karst.;
– Polyporus rubiginosus Fr.;
– Polystictus benzoinus (Wahlenb.) Bigeard & H.Guill.;
– Trametes benzoina (Wahlenb.) Fr.;
– Trametes rubiginosus Fr.;
– Ungulina benzoina (Wahlenb.) Pat., 1900;
– Ungulina benzoina (Wahlenb.) Singer.
Etymology –
The term Ischnoderma comes from the ancient Greek ἰσχνός (ischnos), meaning strong or robust and δέρμα (dermis), referring to the skin or surface.
The specific epithet benzoinum comes from the Latin benzoinus, due to the odor similar to the balsamic resin that oozes from the Styrax benzoin of India.
Geographic Distribution and Habitat –
Ischnoderma benzoinum is a basidiomycete fungus that grows in Europe, especially in the central-northern area, in Siberia, with findings as far as Korea and Japan, in the United States.
Its habitat is almost exclusively on conifers where it develops especially in the autumn period.
Recognition –
Ischnoderma benzoinum is a stemless mushroom with an 8-22 cm carpophore, shaped like a shelf, fixed to the substrate by a dorsal umbo; tomentose then smooth, wrinkled, rusty brown or blackish-brown in colour.
The hymenium is made up of whitish, round-angular pores, 4-6 per mm, in more mature specimens they become brown, darken if touched, brown tubules of about 1 cm in length.
The meat is made up of a context with a thickness of about 1 cm, soft and whitish when young, ocher and hard when mature. It has a fibrous-fleshy consistency, then suberose, yellowish, then tawny.
Under the microscope, cylindrical spores can be seen, white in mass, 4.9-6.0 x 1.4-2.4 µm, non-amyloid, smooth, hyaline.
The basidia are clavate, tetrasporic, with buckle joints at the base, 14.22-18.74 x 3.86-5.68 µm.
The context becomes black-brown with the KOH.
Cultivation –
Ischnoderma benzoinum is a non-cultivated mushroom that bears fruit on stumps and roots of pine and fir trees.
Customs and Traditions –
Ischnoderma benzoinum is a mushroom known in some countries by some common names; among these we report: in France it is known as “Polypore balsamique”, “Polypore à odeur de benjoin”; in Germany “Schwarzgebänderter Harzporling”; in the UK “Benzoin Bracket”.
This genus includes annual basidiomata, sessile, shelf-like, often fan-shaped, initially soft and then very hard, with a tomentose pileus surface which then becomes a crust, dark brown to blackish in colour. Whitish poroid hymenium that darkens when touched. Dimitic hyphal system with fibulated generating hyphae and hyaline or brown skeletal hyphae, cylindrical basidiospores, non-amyloid, smooth, white in mass. Saprotrophic species of conifers and broad-leaved trees, agents of white decay.
It is an inedible and worthless mushroom.
This mushroom is quite widespread in the northern hemisphere, not frequent in Italy. The other species of the genus, Ischnoderma resinosum (Fries) P. Karsten 1879, is very similar macroscopically, but grows exclusively on broad-leaved trees, preferably beech (Fagus sylvatica).
Some possible confusion could arise with Meripilus gigantesus (Persoon) P.Karsten 1882, which however is easily recognizable due to the non-instant blackening to the touch in all its parts, and the preferential growth on Castanea sativa and Fagus sylvatica , furthermore the spores are ellipsoidal and larger 5.5-7.5 × 4.5-6 µm.
It can also be confused with Bondarzewia mesenterica (Schaeffer) Kreisel 1984, which, although sharing the habitat, grows on emerging roots of Picea abies and Abies alba, but has whitish, angular and irregular pores, the same color tubules and context, the hyphae without buckle joints, the spores amyloid, subglobose and warty.
Preparation Method –
Ischnoderma benzoinum is a mushroom with a leathery consistency and unsuitable edibility.
Guido Bissanti
Sources
– Wikipedia, the free encyclopedia.
– GBIF, the Global Biodiversity Information Facility.
– Cetto B., 2008. Mushrooms from life, Saturnia, Trento.
– Pignatti S., 1982. Flora d’Italia, Edagricole, Bologna.
– Conti F., Abbate G., Alessandrini A., Blasi C. (ed.), 2005. An annotated checklist of the Italian vascular flora, Palombi Editore.
Photo source:
– https://inaturalist-open-data.s3.amazonaws.com/photos/309855683/original.jpeg
– https://www.artportalen.se/MediaLibrary/2022/9/1964e151-3880-40a3-ac4d-00d6dc9b69c0_image.jpg
Attention: Pharmaceutical applications and food uses are indicated for informational purposes only, they do not represent in any way a medical prescription; we therefore decline any responsibility for their use for healing, aesthetic or food purposes.