North American Species of Crepidotus

Subgenus Sphaerula subg. nov.

Sporae globosae vel subglobosae; fibulae adsunt.

Spores globose to subglobose; clamp connections present on the hyphae of the pileus cuticle or the gill trama, or at the base of the basidium.

TYPE SPECIES: Crepidotus applanatus (Pers.) Kummer var. applanatus sensu Josserand.

Key to Sections

1. Fruiting body stipitate
Section Nyssicolae
1. Fruiting body sessile or with a pseudostipe
Section Sphaerula

Section Nyssicolae (Singer) stat. nov.

Characters given in the key.

TYPE SPECIES: Crepidotus nyssicola (Murr.) Sing.

1. Pileus deeply depressed, white to cremeous
1. Pileus convex
2. Pileus white to watery white
2. Pileus isabelline or pinkish cinnamon

*See Excluded Species

Section Sphaerula sec. nov.

Pileus sessilis vel pseudo-stipitem gerens.

Spores globose or subglobose; clamp connections present; pileus sessile or with a pseudostipe.

TYPE SPECIES: Crepidotus applanatus (Fr.) Kummer

Key to Subsections

1. Pileus at first white, but may become darker (grayish or brownish) in age or when wet, glabrous or white-fibrillose
Subsection Sphaeruli
1. Pileus or its fibrils colored
2. Pileus at first colored, glabrous or white to buff fibrillose
Subsection Colorantes
2. Pileus surface white or colored at first, bearing brown fibrils
Subsection Fulvifibrillosi

Subsection Sphaeruli

Characters given in the key.

Type species: Crepidotus applanatus (Fr.) Kummer

1. Pleurocystidia present
1. Pleurocystidia absent
2. Spores 4-5.5 µ in diameter
2. Spores 5-7 µ in diameter
3. Pileus developing black spots in age
3. Pileus not as above
4. Spores 4-5.5 µ in diameter
4. Spores 5-7 (8) µ in diameter
5. Lamellae broad or medium broad
5. Lamellae narrow or moderately so
6. Pileus 4-8 (10) mm broad, conchate
6. Pileus 8-25 mm broad, reniform to fan-shaped
7. Pileus tomentose, cuticle bearing a tangled turf; pileocystidia none
7. Pileus glabrose to villose to pruinose
8. Cheilocystidia 20-40 (50) µ long, non-septate, cylindric, clavate, or ventricose, pileocystidia often present, 25-65 µ long
8. Cheilocystidia not as above
9. Cheilocystidia septate, at times forked; pileocystidia up to 60-120 µ long
9. Cheilocystidia non-septate, often forked or contorted; pileocystidia often contorted, forked or branched
10. Lamellae narrow, close or crowded
10. Lamellae broad or very broad
11. Pileus hygrophanous, conspicuously darkening on drying
11. Pileus not as above
12. Pileus becoming fulvous or tawny on drying, glabrous
12. Pileus becoming "Prout's brown" on drying, pubescent to fibrillose
13. Pileus typically very small (6 mm or less)
13. Pileus typically broader
14. Lamellae unusually broad and distant to subdistant
14. Lamellae narrow and close
15. Cheilocystidia cylindric, often capitate
15. Cheilocystidia obclavate, or flask-shaped, or at times fusoid
16. Pileus 4-12 mm broad, white-frosted villose
16. Pileus 10-50 (70) mm broad
17. Pileus glabrous, with few or no erect hyphae; no pileocystidia
17. Pileus villose or pruinose; either pileocystidia or a hyphal-turf present
18. Pileocystidia present; cheilocystidia non-septate
18. Pileocystidia none, a turf present; cheilocystidia at times septate

*See Excluded Species

Subsection Colorantes subsec. nov.

Pileus maturus coloratus, glabrosus vel fibrillas albas aut coriaceas gerens.

Pileus colored at maturity, glabrous, or with white or buff fibrils.

TYPE SPECIES: Crepidotus confertus.

1. Spores 4-5 (5.5) µ in diameter
1. Spores 5-7 (8) µ in diameter
2. Lamellae narrow or moderately so
2. Lamellae broad to medium broad
3. Pleurocystidia present; pileus buff
3. Pleurocystidia absent; pileus color not as above
4. Cheilocystidia clavate or ventricose
4. Cheilocystidia filamentous to cylindric, flexuous
5. Pileus yellowish or becoming so
5. Pileus brownish or tawny at first
6. Pileus at first gray, then yellow, finally brownish
6. Pileus yellowish, unchanging
7. Pleurocystidia present
7. Pleurocystidia absent
8. Pileus pale tawny, dull cinnamon or brown
8. Pileus gray, then yellow, then brown
9. Pileus deeply sulcate
9. Pileus not sulcate
10. Pileus cuticle of 3-6 (8) layers of repent hyphae
10. Pileus cuticle not as above
11. Cheilocystidia irregularly shaped, flexuous or contorted
11. Cheilocystidia regularly shaped, not contorted
12. Cheilocystidia 2-8 µ broad, at least some flexuous or sinuous; gills orange buff
12. Cheilocystidia 7-13 µ broad, strongly contorted (forked, knobbed, branched); gills white or grayish yellow, becoming brownish
13. Lamellae narrow or moderately so; pleurocystidia present
13. Lamellae broad or medium broad, at least in age, pleurocystidia absent
14. Pileus pink, at least when mature
14. Pileus tawny
15. Pileus varicolored: white with pallid spots and buff tints, margin drab to cinnamon brown
15. Pileus not as above
16. Pileus yellowish; cheilocystidia 25-72 µ long; pileocystidia present, cylindric, clavate, at times crooked or coiled
16. Pileus ochraceous; cheilocystidia 26-36 µ long; pileocystidia none

*See Excluded Species

Subsection Fulvifibrillosi subsec. nov.

Pileus coloratus vel albus, hyphas brunneas fortasse incrustatas gerens.

Pileus colored or white, bearing brown, incrusted, or non-incrusted hyphae.

TYPE SPECIES: Crepidotus nephrodes (B. & C.) Sacc.

1. Pleurocystidia present
1. Pleurocystidia absent
2. Spores smooth; pileus bright orange-tawny
2. Spores punctate
3. Cheilocystidia irregularly branched, forked, or contorted
3. Cheilocystidia regular in form
4. Lamellae at first white
4. Lamellae at first colored
5. Lamellae at first pallid-avellaneous
5. Lamellae yellowish or orange at first
6. Pleurocystidia 9-15 µ broad, spathulate, clavate, or ventricose
6. Pleurocystidia 4-9 µ broad, often with a long, slender neck
7. Lamellae at first yellow or orange
7. Lamellae at first whitish, pallid or grayish