Hohenbuehelia (Pleurotaceae) - click to expand
Somewhat gelatinous flesh and metuloid cystidia, but in
practice hard to tell apart from other genera. Species in this family can trap and consume nematodes so they are
carnivorous.
Species mentioned:
Hohenbuehelia angustata, cyphelliformis, mastrucata, petaloides, tremula,
thornii, unguicularis, nigra. Resupinatus niger.
Hohenbuehelia tremula EU
(Hohenbuehelia petaloides EU misapplied) - unique for sometimes being found on the ground on
buried wood, as well as attached to logs. Medium sized (~5cm)
shoehorn shaped brown cap and stem (dark or pale brown) usually
found in the spring. It was long thought
that our local species was Hohenbuehelia petaloides EU, but a WA and OR
sequence are much closer to a type sequence of the lookalike H. tremula,
which has larger spores (>7.5u). Our local sequences are a few bp different from the type of
H. tremula, but EU and local sequences intermingle so I think ours is
the real species. Perhaps local collectors who thought they were finding H.
petaloides were not checking the spore size carefully enough, but I think some sources were inaccurate about what spore sizes to
expect. If you think you actually find H. petaloides, with spores
generally <7.5x4.5u, save it.
Hohenbuehelia thornii EU
- this lookalike on soil is said to have a gelatinous cap cuticle
and is usually found in the fall. It was not known from the PNW until
discovered by DNA. We have two WA collections matching the ITS type sequence
exactly. The mature photo suggests a tan to
grey
cap.

Hohenbuehelia 'tremula PNW01' © Brandon Matheny and Andrew Parker,
H. thornii © Yi-Min Wang and Buck McAdoo
Hohenbuehelia 'angustata PNW02'
- a very non-descript tan oyster resembling a medium sized (5
cm or so) stemless Pleurotus. Unlike the above H.
petuloides-like species, this grown on logs, has gills that go
most or all of the way to the wood,
and a convex tan cap instead of a shoehorn shape. One collection was
noted to smell strongly farinaceous and have copious rhizomorphs. Our two local sequences
are 6 bp and 2 ambiguous locations different from an east coast type sequence of this
Ohio species. Many east coast sequences match the type exactly, so ours
probably needs a new name. H. angustata was reported from here 50
years ago, and only now are we figuring out what those finds probably
represented.
Hohenbuehelia cf mastrucata EU
- a beautiful, larger (~5 cm) grey scaly stemless oyster covered in
gelatinous spines with close, pale gills, found on logs. We have an EU type
sequences, but need local sequences to verify that is what is being found
here.
Hohenbuehelia 'angustata PNW02' © Andrew Parker, H.
cf. mastrucata © Leah Bendlin
Hohenbuehelia 'auriscalpium
PNW03' - a smaller, tan to grey earpick shaped
(distinctly stemmed) Hohenbuehelia on
logs, with some cap scurfiness. It was never known from the PNW before this WA collection.
Tan and scurfy when young, it appears to become grey and scaly/furry in age,
like the larger stemless H. mastrucata. Our sequences are 4%
different in ITS from EU type area sequences.

Hohenbuehelia 'auriscalpium
PNW03' © Yi-Min Wang, Alan Rockefeller and Harte Singer (2 images)
The following tiny, fuzzy grey oysters (a few mm across) with
elliptical spores and metuloids are reported from the PNW, and we
have all their type sequences, but we don't have local DNA of any of them
yet to figure out which ones are really here. We need collections of them
all. One report is of a species of Resupinatus with metuloids that is
therefore difficult to differentiate from Hohenbuehelia, but the
Resupinatus has more closely spaced gills. What we have found locally so
far is a tiny, black Resupinatus without metuloids and with round
spores, discussed on the Resupinatus
page.
Hohenbuehelia cf cyphelliformis UK -
very small (<1 cm) grey felty cap and bright white distant
gills (just a few of them). There have been only a couple unverified
reports from BC.
Hohenbuehelia cf unguicularis EU - another very
small (<1 cm) grey felty capped oyster with darker widely
spaced gills. Rumour has it that it has been found in BC, perhaps up north.
See also Resupinatus, next. We need collections of all of them for
verification.