Biological Species in Pleurotus
RONALD H. PETERSEN, KAREN W. HUGHES, AND NADEZHDA PSURTSEVA
Keys
Keys abound for limited groups (Vilgalys et al., 1993, for the P. ostreatus complex) or of limited accuracy (Pilát, 1935; Kühner and Romagnesi, 1953; Hilber, 1982, 1993, 1997).
To devise a key to this group is fraught with problems, for basidiome colors, hosts, and stature often intergrade, and geographical distribution is often wide and therefore creates overlaps. Especially vexing is the separation of Pleurotus pulmonarius from its sister monomitic, pleurotoid species, P. ostreatus and P. populinus. With these problems in mind, the following key to biological species is offered.
1. Anamorphic spores produced on basidiomata or associated vegetative mycelium ……..……… 2
1. Anamorphic spores, if formed, not associated with basidiomata ………………………………...... 4
2. Anamorphic state a lawn of simple conidiophores producing black arthrospores, dry initially but
later slimy; Australa, New Zealand. ………………………………………………................ P. australis
2. Anamorph coremioid, with black, slimy heads of arthrospores …………………….………........… 3
3. Pileus pale tan to brown; distribution roughly pantropical …………………......…….. P. cystidiosus
3. Pileus deep olive, olive-black, occasionally with purplish tints;
New Zealand, Australia …………………………………………...........………. P. purpureo-olivaceus
4. Stipe central to weakly eccentric ………………………………………………....................…..….…… 5
4. Stipe strongly eccentric or lateral ………………………………………………....................…….….. 11
5. Pileus tan, brown, rufous brown, usually concave ……………………………….…..............………. 6
5. Pileus pearl gray, white, or banana yellow …………………………………………….................…… 8
6. Basidiomata arising from a sclerotium ……………………………………...........… P. tuber-regium
6. Basidiomata without sclerotium ……………………………………………………….................……. 7
7. Root parasite; pileus tan to brown; Europe ……………………………………..........…….. P. eryngii
7. On rotting wood; pileus tan, brown, usually with ruddy tints ………………….....… P. cornucopiae
8. Pileus and stipe white to pearl gray …………………………………………………...............……… 9
8. Pileus banana yellow; stipe white (citrinopileatus form) ……………………......… P. cornucopiae
9. Stipe nearly lateral; on Agave, Opuntia; northern Africa, Mexico ……………….......… P. opuntiae
9. Stipe central; all basidiome parts white ……………………………………………...........…..…… 10
10. Pileus surface velutinous to plushy; warm climates; anamorph unknown ………......... P. levis
10. Pileus surface strigose to wooly; cool, wet climates; anamorph of tan to brown
arthrospores in culture …………………………………………………………..............…. P. dryinus
11. Stipe tissue dimitic ……………………………………………………………………................…. 12
11. Stipe tissue monomitic ………………………………………………………...……...............…… 14
12. Partial veil present over young lamellae …………………………………......……… P. calyptratus
12. Partial veil absent …………………………………………………………………..................…….. 13
13. Basidiomata usually everted; pileus surface ruddy tan to ruddy brown …….… P. cornucopiae
13. Basidiomata pleurotoid; pileus surface white, yellow-olive, brown,
olive-brown, pink or gray ………………………………………………………...............… P. djamor
14. On coniferous wood; northern China, far eastern Russia ………………………... P. abieticola
14. On deciduous wood (chiefly) ………………………………………………………...............……. 15
15. Pileus and lamellae buffy tan to pastel tan; lamellae subdistant;
spore print pallid buff; spores 9-12 X 3-5 m m; North America; usually on
Populus wood ……………………………………………………………..................….. P. populinus
15. Pileus various shades of off-white, tan, brown, deep gray, bluish olive
to olive-black; spore print avellaneous; spores 7-10 m m long; worldwide;
usually on deciduous wood ……………………………………………………………...........….. 16
16. Fruiting predominately in winter; pileus tan, brown, gray-brown, olive-black;
North Temperate Zone ………………………………………………………...........…. .P. ostreatus
16. Fruiting predominately in late summer (Europe, Asia, eastern North America) or
spring (western North America); pileus white, tan, gray-brown; North
Temperate Zone …………………………………………………………............….. P. pulmonarius