A
- Cortinarius abditus – France
- Cortinarius aberrans – France
- Cortinarius abietinus
- Cortinarius abnormis – Western Australia
- Cortinarius absarokensis – USA (Montana)
- Cortinarius absinthiacus – Argentina
- Cortinarius acerbiformis – France
- Cortinarius acerbus – Argentina
- Cortinarius achrous – New Zealand
- Cortinarius achyrocephalus
- Cortinarius aciculisporus – France
- Cortinarius acidophilus – Norway
- Cortinarius acigemmascens – France
- Cortinarius aciserratus
- Cortinarius acutellus – France
- Cortinarius acutibulbus – France
- Cortinarius acutispissipes – France
- Cortinarius acutoaltus – France
- Cortinarius acutocephalus – France
- Cortinarius acutus
- Cortinarius adustus
- Cortinarius aggregatus
- Cortinarius albidus – (North America)
- Cortinarius alboviolaceus – silver-violet webcap (Europe)
- Cortinarius amethystinus
- Cortinarius amoenelens = C. cyanopus
- Cortinarius angulosus
- Cortinarius anomalus
- Cortinarius archeri – (Australia)
- Cortinarius argentatus
- Cortinarius argyrionus
- Cortinarius armeniacus
- Cortinarius armillatus – bracelet cortinar (North America)
- Cortinarius atkinsonianus
- Cortinarius aurantiobasis – edible, but deadly look-alikes (C. gentilis)
- Cortinarius aureifolius – edible, but deadly look-alikes (C. gentilis)
- Cortinarius aureofulvus
- Cortinarius australiensis (previously Rozites australiensis)
- Cortinarius austrovenetus - also known as Dermocybe austroveneta Green Skin-head (Australia)
Read more about this topic: List Of Cortinarius Species