Pseudoclitocybaceae

© Bruce Newhouse

Danny’s DNA Discoveries – Pseudoclitocybaceae of the PNW (Tricholomatineae)
by Danny Miller

Introduction

The genera in this family are very, very similar. I don't think they should necessarily have been split, so feel free to think of these greyish brown funnel caps with strongly decurrent gills and indented caps in age collectively as Pseudoclitocybe s.l. or the Pseudoclitocybaceae. Even an ITS only tree shows these three genera cluster closely together in a family in the Tricholomatineae sub-order. They may or may not have clamp connections and inamyloid spores like Clitocybe, which they are easily confused with.

Pseudoclitocybe - has smooth, amyloid spores (unlike Clitocybe's inamyloid spores).

Harmajaea - a large, chalky-grey funnel cap that may be felty with a sometimes disagreeable odor and taste and possible greying flesh with smooth inamyloid spores like Clitocybe (and only recently separated on molecular evidence) but unlike most Clitocybe, lacking clamp connections. The lack of clamp connections may be the only reliable way to separate it from Clitopaxillus.

Clitopaxillus - a very similar large chalky-grey funnel cap that also may be felty that browns in age with a mild odor/taste. It has smooth inamyloid spores and clamp connections, and therefore the hardest to separate from Clitocybe.

Aspropaxillus - one of our largest gilled mushrooms, a huge funnel-shaped clitocyboid up to 40cm across. Clitocybe maxima and Infundibulicybe geotropa may also get large. Unpleasant odor and taste. Formerly in Leucopaxillus because the gills separate easily, but although large, these are not as dense as Leucopaxillus. Amyloid spores.

abundant common uncommon rare - colour codes match my Pictorial Key and are my opinions and probably reflect my bias of living in W WA. Rare species may be locally common in certain places at certain times.

Pseudoclitocybe - click to expand
large grey-brown funnel shaped clitocyboids with smooth, amyloid spores (unlike Clitocybe's inamyloid spores). When young, they may have quite an inrolled cap margin.
Species mentioned: Pseudoclitocybe cyathiformis, expallens, oregonensis.

Pseudoclitocybe cyathiformis EU - somewhat variably coloured. Two WA sequences match an overwhelming number of EU sequences quite well.
Pseudoclitocybe expallens EU - very similar species but usually found in grasslands and paler (especially when drying out) as seen in the first photo, but sometimes darker and found in forests just like P. cyathiformis (see the second photo, showing the inrolled cap margin when young). This represents 'P. cyathiformis II', a sister species in the Pseudoclitocybaceae paper. We don't have a type sequence to know what P. expallens really is for sure, but one theory is that it is this species, as it was described as being very much like P. cyathiformis.
Pseudoclitocybe cf oregonensis OR - appears to have gills just as dark as the cap and stem. As mentioned under Cantharellula, this species is likely a Pseudoclitocybe, although it is sometimes referred to as Cantharellula oregonensis, but without a type sequence we can't prove it. We do have local DNA of a Pseudoclitocybe in OR and CA that is 4% different than Pseudoclitocybe obbata EU, and this DNA is thought to represent P. oregonensis. If it does not, then these collections need a new name and we need to figure out what P. oregonensis really is.

Pseudoclitocybe cyathiformis © NAMA & the Field Museum of Natural History and Danny Miller

Pseudoclitocybe expallens © Yi-Min Wang (2 images), P. cf. oregonensis © Bruce Newhouse

Harmajaea - click to expand
A large, chalky-grey funnel cap that may be felty with a sometimes disagreeable odor and taste and greying flesh. The margin may be inrolled and the cap may have water spots. It has smooth inamyloid spores like Clitocybe (and only recently separated on molecular evidence) but unlike most Clitocybe, lacking clamp connections. The lack of clamp connections and sometimes disagreeable odor may be the only reliable way to separate it from Clitopaxillus, next.
Species mentioned: Harmajaea harperi.

Harmajaea harperi CA - we have 3 WA sequenced collections, very probably representing this CA species, especially since EU ITS DNA is the same, so CA is not likely to have a different species even though we don't have the type sequence.

Harmajaea harperi © Jacob Kalichman

Clitopaxillus - click to expand
very similar large chalky-grey funnel cap that also may be felty that browns in age with a mild odor/taste. The margin may be inrolled and the cap may have water spots. It has smooth inamyloid spores and clamp connections, and therefore the hardest to separate from Clitocybe. The clamp connections and always mild odor may be the only reliable way to separate it from Harmajaea, above.
Species mentioned: Clitopaxillus alexandri. Clitocybe crassa, leopardina.

Clitopaxillus PNW01 - we have EU DNA of C. alexandri, and our one local sequence is 3% different in ITS, suggesting that we have a distinct species. It may be Clitocybe leopardina OR, which would need to be moved to Clitopaxillus. Another unknown Clitocybe, Clitocybe crassa ID needs to be investigated to see what it is. It could also belong in Clitopaxillus. Bigelow also reported the true Clitopaxillus alexandri EU from the PNW, so more collections are needed to see how many species of Clitopaxillus occur here.

Clitopaxillus PNW01 © Jacob Kalichman

Aspropaxillus - click to expand
One of our largest gilled mushrooms, a huge funnel-shaped clitocyboid up to 40cm across. Clitocybe maxima and Infundibulicybe geotropa may also get large. Unpleasant/farinaceous odor and taste. Formerly in Leucopaxillus because the gills separate easily, but although large, these are not as dense as Leucopaxillus. Amyloid spores.
Species mentioned: Aspropaxillus giganteus, septentrionalis.

Aspropaxillus septentrionalis OR - strongly unpleasant odor and taste. Possible clustered growth and possible notched gills with a decurrent tooth. We have the holotype sequence and matching sequences from WA and OR. However, even collections with a farinaceous odor and strongly decurrent gills (supposedly A. giganteus) sequence to be this species, so I don't think we actually have A. giganteus in the PNW.
Aspropaxillus giganteus EU - said to never grow clustered and have more traditionally decurrent gills and a weaker farinaceous/unpleasant taste, but this EU species has not been confirmed from the PNW, and in fact collections matching this description also sequenced to be A. septentrionalis.

Aspropaxillus septentrionalis © Jonathan Frank

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