Key to genera in the Agaricaceae in California ~ Else C. Vellinga ~ May 2004
Key to agaricoid members of the Agaricaceae, including Lepiotaceae, in California
Based on both macroscopical and microscopical characters
Else C. Vellinga
vellinga@berkeley.edu
1.Spores brown, dark or black
2. Spores black, with a germ pore; pileus dissolving into ink
................................................................................... Coprinus comatus and C. sterquilinus
2. Spores red to brown, without a germ pore or with an inconspicuous germ pore; pileus never
dissolving into ink
3. Lamellae pink-red; pileus small (c. 1 cm), dark brownish, with granulose covering, made up
of round cells; spores rough and warted
.......................................................Melanophyllum haematospermum (in Redwood forests)
3. Lamellae pale pink at first, changing to dark brown with age; pileus small to very big and
fleshy, smooth or with fibrillose to scaly covering; spores smooth............................. Agaricus
1. Spores white or very pale, or green(ish)
4. Spores green ...............................................................................Chlorophyllum molybdites
4. Spores white
5. Spores with a germ pore AND clamp connections present at base of basidia
6. Spores with a truncate apex, without a hyaline cap over the pore; stipe smooth
................................................. Chlorophyllum, including Macrolepiota rachodes and allies
6. Spores with a rounded apex, and a hyaline cap over the pore; stipe with small flocks in
bands............................................................................ Macrolepiota (very rare in California)
5. Spores without a germ pore, or with a germ pore but then without clamp connections
7. Pileus with a granulose covering, made up of round cells; spores small; clamp connections
present or absent................................................................................................. Cystolepiota
7. Pileus with a smooth or squamose covering, made up of elongated cells, rarely with round
cells; clamp connections absent or present
8. Clamp connections present (check in pileus covering or at base of basidia) ........... Lepiota
8. Clamp connections absent
9. Pileus covering made up inflated cells; spores small, without germ pore
.................................................................Cystolepiota pulverulenta/Lepiota petasiformis
9. Pileus covering very variable, if made up of inflated cells, spores with germ pore and
relatively big ..................................................................... Leuoagaricus & Leucocoprinus
....(molecular data indicate that these two genera are intermingled, and can not be separated)
How to recognize a Lepiota species from a Leuocagaricus species
Lepiota - Stipe woolly or with material in bands as on cap. If stipe is smooth, without such
material, clamp connections are present, and the pileus covering is a hymeniderm.
Leucoagaricus - Stipe smooth, or at the utmost with the same colour as the pileus; pileus
covering mainly thin. If in doubt get the microscope out: clamp connections absent and spores
have a pink inner wall in Cresyl Blue.