Leccinum Gray
Many species are known in Europe, although recent molecular studies have reduced significantly their number. Although the reader will find numerous references bellow, they should always consult the treatment of Den Bakker & Noordeloos (2005), some of its results also partly available online (see Noordeloos, online) in the form of a key, descriptions and photographs. Useful keys (excluding two south European species) are provided also by Kibby (2006) and Knudsen & Vesterholt (2008). Everybody reading those pages have to bear in mind that identification of Leccinum currently relies on both macroscopic and microscopic characters.
Fruitbody boletoid without veil and ring. Stipe solid, covered with numerous squamules. Flesh whitish or yellowish, sometimes spotted blue or greenish in the stipe base, in many species changing dramatically to pinkish, reddish, violaceous grey to black.
Leccinum crocipodium (Letell.) Watling
I am not providing information for this species, but some photographs are seen below. Click here to go to Machiel Noordeloos’ page on Leccinum, where detailed description and other information is provided. Leccinum nigrescens is sometimes used for this species.
Photographs
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Young and fully developed fruitbodies of Leccinum crocipodium. (photo B. Assyov)
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Another ample collection of Leccinum crocipodium. (photo B. Assyov)
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Fruitbodies of Leccinum crocipodium. Note the stipe ornamentation. (photo I. Assyova)
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Mature fruitbody of Leccinum crocipodium. The yellow pores are notable feature of this species. (photo B. Assyov)
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Fruitbody of Leccinum crocipodium. The cap usually becomes darker and cracked with age. (photo B. Assyov)
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Fruitbodies of Leccinum crocipodium. Note the colour change of the flesh that immediately turns reddish violet when exposed. (photo B. Assyov)
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Leccinum crocipodium. After prolonged exposure to air the reddish or greyish violet stained flesh becomes dark grey to almost blackish. (photo B. Assyov)
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Spores of Leccinum crocipodium. Scale bar = 10 μm. (photo B. Assyov)
Important literature
Alessio, C.L. 1985. Boletus Dill. ex L. (sensu lato). – In: Fungi Europaei. Vol. 2. Pp. 1–705. Libreria editrice Biella Giovanna, Saronno.
Breitenbach J. & Kränzlin F. 1991. Pilze der Schweiz. Bd. 3(1). Röhrlinge und Blätterpilze. Verlag Mykologia, Luzern.
Den Bakker, H.C. & Noordeloos, M.E. 2005. A revision of European species of Leccinum Gray and notes on extralimital species. – Persoonia 18: 511–587.
Engel, H. 1983. Rauhstielröhrlinge. Die Gattung Leccinum in Europa. Verlag Heinz Engel, Weidhausen b. Coburg.
Estadès, A. & Lannoy, G. 2004. Les bolets européens. – Bulletin Mycologique et Botanique Dauphiné-Savoie 44(3): 3–79.
Galli, R. 1998. I Boleti. Atlante pratico-monographico per la determinazione dei boleti. Edinatura, Milano.
Kibby, G. 2006. Leccinum revisited. A new synoptic key to species. – Field Mycology 7(4): 77–87.
Knudsen, H. & Vesterholt, J. [eds.]. 2008. Funga Nordica. Nordsvamp, Kopenhagen.
Lannoy, G. & Estadès, A. 1995. Monographie des Leccinum d’Europe. Fédération Mycologique Dauphiné-Savoie.
Lannoy, G. & Estadès, A. 2001. Les Bolets. Flore mycologique d’Europe. Documents Mycologiques Mémoire Hors série no. 6. Pp. 1–163. Association d’Écologie et de Mycologie, Lille.
Noordeloos, M. (online). The genus Leccinum in Northern and Central Europe. http://www.entoloma.nl/html/leccinum_eng.html
Muñoz, J.A. 2005. Boletus s. l. – In: Fungi Europaei. Vol. 1. Pp. 1–951. Edizioni Candusso, Alassio.
Šutara, J., Mikšík, M. & Janda, V. 2009. Hřibovité houby. Čeled’ Boletaceae a rody Gyrodon, Gyroporus, Boletinus a Suillus. Academia, Praha.