Cystolepiota – else c vellinga 5 June 2007, vellinga@nature.berkeley.edu / ecvellinga@comcast.net

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Key to the Cystolepiota species in western North America 1. Stipe and pileus with lilac and violaceous tinges; smell strong, of coal gas (indole), like the smell of Tricholoma sulphureum and T. inamoenum ..............................................C. bucknallii

1. Stipe and pileus pinkish, white, or whitish and often discolouring with age, without lilac or violaceous tinges, and not smelling of coal gas, but of Lepiota cristata 2. Pileus covering copious, made up of elongate inflated irregular cells; spores rough; clamp connections absent ............................................................................................C. petasiformis 2. Pileus covering made up of globose cells; spores smooth; clamp connections present 3. Basidiocarps slender; pileus small (about 1 cm, rarely up to 2 cm) and white; stipe vinaceous, especially at base; cheilocystidia absent ............................................. C. seminuda 3. Basidiocarps slender to quite robust, with pink pileus, or starting out white and discolouring isabelline to rust brown; cheilocystidia present 4. Pileus covered with small pink granulose warts ................................................C. moelleri 4. Pileus covered in isabelline or rusty brown floccose granular velum 5. Basidiocarp with age with isabelline colours; pleurocystidia abundant over entire surface of lamellae; pleurocystidia and cheilocystidia with yellow contents and exudates .....................................................................................................................C. fumosifolia 5. Basidiocarp with rusty brown colours with age; pleurocystidia absent; some yellow contents or exudates can be present in cheilocystidia ..................................C. oregonensis

Cystolepiota – else c vellinga 5 June 2007, vellinga@nature.berkeley.edu / ecvellinga@comcast.net

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Miscellaneous notes to the species Cystolepiota bucknallii (Berk. & Br.) Singer & Clém. is mentioned in Arora’s and Sieger’s keys, but has not been found in California by Sundberg (1967) nor by me (ecv). However, it has been collected a few times in the north-western part of the state by David Largent and his students (Largent, pers. comm., 2007). It differs from the other species not only in the unusual colours, but also in microscopical characters: the spores are exceptionally long and dextrinoid in Melzer’s reagent (though the reaction can be slow), whereas in the other species the spores are ellipsoid, and not dextrinoid. Cystolepiota fumosifolia (Murrill) Vellinga was described from Washington. Later, this same species was described as L. cystidiosa A.H. Sm. from Michigan. It is a sturdy species, easily recognized by the yellow stuff surrounding the (abundant) cheilo- and pleurocystidia. It is not a common species, but has been found in the north of California, and in Washington. It looks very much like C. petasiformis in the field. Cystolepiota moelleri Knudsen is known from the state of Washington. It has a pink pileus with small granular warts, and cheilocystidia with an apical excrescence. Cystolepiota oregonensis (H.V. Sm.) Vellinga is a small species, with reddish brown discolouration, and not as copiously provided with velar material on the pileus as C. fumosifolia and C. petasiformis. It is very similar to the European species C. hetieri; the latter is also recorded for Washington (Sieger 2003). Clamp connections are present, though not noted in the original species description. It has not yet been reported from California, but occurs in Oregon and Washington. Cystolepiota petasiformis (Murrill) Vellinga is an oddball in the genus, because of the absence of clamp-connections, the non-globose cells of the veil, and the roughened spores, sometimes weakly and slowly dextrinoid. The pileus is often conical because of the copious veil, but you can blow off these cells. It has been found throughout the western states, but is not common. The European species C. pulverulenta is identical. Cystolepiota seminuda (Lasch) Bon is the most common species of the group, but its fruitbodies are small and not very conspicuous, also because they often grow solitary or in small groups. It occurs in all kinds of woods and forests. Lepiota pusillomyces and L. hemisphaerica are synonyms. This species occurs all through the temperate parts of the Northern Hemisphere. Further reading: Arora, D., 1986. Mushrooms demystified. 2nd Ed. Berkeley, TenSpeed Press. 959 pp. Sieger, R.E., 2003. Trial Key to Pacific Northwest Lepiota and Allies. Pacific Northwest Key

Council. 24 pp. Sundberg, W.J., 1967. The family Lepiotaceae in California. Master's thesis, San Francisco State

University. 219 pp. Vellinga, E.C., 2001. Cystolepiota. In Noordeloos, M.E., Th.W. Kuyper & E.C. Vellinga (eds).

Flora agaricina neerlandica 5: 154-160. Lisse/Abingdon/Exton (PA)/Tokyo A.A. Balkema Publishers. 169 pp.

Vellinga, E.C., 2007. Lepiotaceous fungi in California, U.S.A. – 4. Type studies of Lepiota fumosifolia and L. petasiformis. Mycotaxon 98: 225-232.