Hemileccinum impolitum
| Hemileccinum impolitum | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Basidiomycota |
| Class: | Agaricomycetes |
| Order: | Boletales |
| Family: | Boletaceae |
| Genus: | Hemileccinum |
| Species: | H. impolitum
|
| Binomial name | |
| Hemileccinum impolitum (Fr.) Šutara (2008)
| |
| Synonyms[1] | |
Hemileccinum impolitum | |
|---|---|
 | Pores on hymenium |
 | Cap is convex or flat |
 | mycorrhizal |
 | Edibility is edible |
Hemileccinum impolitum is a
Like other members of the family, H. impolitum has tubes and pores instead of
Taxonomy and phylogeny
The iodine bolete was first described by Elias Magnus Fries, an eminent mycologist of the 19th century, who placed the fungus in genus Boletus.[2] The Latin epithet impolitum (meaning "rough"), likely refers to the cap of the species, which is initially felty and covered in a finely filamentous coating when viewed under a magnifying glass. The species' taxonomic position had long remained uncertain and various authors had placed it in different genera in the past, including the now abandoned genera Tubiporus[3] and Versipellis.[4]
Based on preliminary analysis of the
Description
The cap diameter usually ranges between 5 and 12 cm (2 and 4.5 in), but can reach 20 cm (8 in). It is at first hemispherical, gradually becoming convex as the fungus expands and finally flat in fully mature specimens, sometimes with a slightly uplifted margin. The colour ranges from light tan, pale brown, chestnut-brown, grey, ochraceous-brown, greyish-brown or olivaceous-brown and the cap of young fruit bodies is initially covered in a velvety, finely filamentous silvery-grey coating that disappears in age.[9][10]
The
The stem is cylindrical, clavate or ventricose, 5 to 15 cm (2 to 6 in) high by 2 to 6 cm (1 to 2.5 in) wide, cream to pale yellow, but typically lemon-yellow at the apex and usually narrowing at the base. It has no reticulation (net), but is covered in tiny pustules (scabrosities) below the apex, sometimes browning with age.[11][1]
The tubes are pale yellow to lemon-yellow and usually do not discolour when cut, but may rarely stain faintly greenish-brown. The pores are small and rounded, lemon-yellow to chrome-yellow, not discolouring or rarely staining greenish-brown where handled or injured. The flesh is thick, soft, pale yellow to whitish, usually remaining the same colour when cut, or rarely becoming faintly pinkish-brown above the tubes and at the stem base. It has a sour smell somewhat reminiscent of iodine, more pronounced at the stem base.[12][11]
The spore print is olivaceous-brown.[13]
The spores are fusiform (spindle-shaped) or fusiform-ellipsoid, measuring 10–16 × 4–6 μm.[14] Although under an optical microscope they appear perfectly smooth, when viewed with a scanning electron microscope (SEM) fine warts and tiny “pin-pricks” are visible on their surface.[6] The cap cuticle is a trichodermium, composed of cylindrical smooth hyphae with clavate terminal cells that later collapse in mature specimens.[1]
Similar species
- Hemileccinum depilatum is the sister-species of H. impolitum and morphologically very similar, differing by its wrinkled or "hammered" cap surface, and its association hornbeam (Carpinus) or hop-hornbeam (Ostrya). Microscopically it is distinguished by the structure of its cap cuticle, which is a palisadoderm composed of spherical and shortly cylindrical cells.
- Leccinellum lepidum can also look very similar, but typically has a viscid cap with a wrinkled or "hammered" surface not turning violet with a drop of aqueous ammonia, while its flesh slowly turns violaceous-grey and finally greyish-black when exposed to the air. Microscopically it has longer spores, often reaching 20 μm in length.
- Xerocomus subtomentosus lacks scabrosities on the stem surface, while its pores are larger, angular and stain bluish when bruised. When longitudinally cut, its flesh is pinkish-brown in the lower part of the stem and sometimes discolours faintly bluish in the cap.
Distribution and habitat
Hemileccinum impolitum is ecologically versatile, forming
Edibility
The iodine bolete is described as edible by some authors,[10][17] and inedible by others,[14] probably because of the peculiar odour of this species. However, it is hardly ever found in large numbers, therefore care and discretion should be exercised when intending to eat this mushroom.
References
- ^ .
- ^ Fries, E. (1838). Epicrisis Systematis Mycologici. :1-610
- ^ Karsten PA. (1882). Rysslands, Finlans och den Skandinaviska halföns Hattsvampar. Sednare Delen: Pip-, Tagg-, Hud-, Klubb- och Gelésvampar. Bidrag till Kännedom av Finlands Natur och Folk. 37: 1–257
- ^ Quélet L. (1886). Enchir. fung. (Paris): 158
- ^ Binder M, Besl H (2000). 28S rDNA sequence data and chemo-taxonomical analyses on the ge- neric concept of Leccinum (Boletales) (in German). Trento: Verlag Micologia 2000.
- ^ S2CID 15652037.
- ^ S2CID 82844711.
- ^ S2CID 181958289.
- ^ Courtecuisse R, Duhem B (1995). Mushrooms & Toadstools of Britain & Europe. London, UK: Harper-Collins.
- ^ a b c Galli R. (2007). I Boleti. Atlante pratico-monographico per la determinazione dei boleti (in Italian) (3rd ed.). Milano, Italy: Dalla Natura.
- ^ ISBN 978-88-901057-2-2.
- ISBN 0-330-44237-6.
- ISBN 1-85223-592-6.
- ^ ISBN 978-3-85604-030-7.
- ^ Watling R, Hills AE (2005). "Boletes and their allies (revised and enlarged edition)". In Henderson DM, Orton PD, Watling R (eds.). British Fungus Flora. Agarics and boleti. Vol. 1. Edinburgh, Scotland: Royal Botanic Garden.
- ^ Kibby G (2016). British Boletes: with key to species (7th ed.).
- ISBN 978-1-55407-651-2.