Ascomycete Wannabes: Cyphelloid Fungi—Part II

The first cyphelloid fungus I found was Henningsomyces candidus. These are tiny, usually snow white, hairy tubules that cluster on the undersides of rotting logs. Though they occasionally reach an astonishing length of three millimetres, their diameter maxes out at only a sixth of that. Tiny, as I said. They can, however, grow in large enough communities that the white patches are easily seen. You just can't tell how startlingly odd they are until you look at them under magnification.

Henningsomyces candidus (Boleslaw Kuznik, Mushroom Observer)

Nia vibrissa

In my first post about cyphelloids I promised a weirder link between not-very-similar-looking fungi. This is where we bring in Nia vibrissa, another minute guy. N. vibrissa has a couple of very interesting things going for it. First off, it's a marine fungus. Yes, that's right, it's an underwater saprophyte that can be found all over the world on different types of submerged wood, including mangroves and sunken ship timber. Secondly, it's not a cyphelloid fungus, it's a gasteroid: like puffballs, it produces its spores inside its fruiting body instead of on the surface. The third thing (if I have this right) is that there's phylogenetic evidence that shows a sister group relationship between the Henningsomyces candidus I found and Nia vibrissa. Which means that N. vibrissa is likely a reduced form of a reduced form (see Part I). 

What goes around, comes around: the earliest ancestors of our contemporary terrestrial fungi are thought to have evolved from simple, flagellated aquatic forms.

Some Henningsomyces candidus are barely tubular.

A Fistulina Connection

There is also evidence, though weakly supported, that the Nia/
Henningsomyces clade is sister to the non-cyphelloid Schizophyllum/
Fistulina clade.

Fistulina hepatica, the Beefsteak Polypore.

If you look closely at some of the hairy cyphelloids in the Nia clade, i.e. Henningsomyces and Merismodes species, and compare them to the spore-producing tubes of Fistulina hepatica, it's hard not to see a resemblance, a resemblance that was noted long before DNA analysis was possible. 

Cross-section and close-up of Fistulina hepatica tubes.

When tiny, hairy Merismodes cups are not fully open, there are similarities
to Fistulina hepatica's spore producing structures.

Merismodes

I found several Merismodes species last winter on dead branches fallen from trees (one of which I wrote about here). Merismodes spend a lot of their time looking like hairy little nubbins—until they're offered some moisture and open up into hairy little cups. They're not the only cyphelloids that go into dormancy in drought and revive when moisture returns.  

Calathella eruciformis

Wading through deep snow in March, I investigated some pale dots on a dead Populus branch, dots that turned into down-hanging goblets with pinched "stems" when I looked at them through my hand lens after waking them up in the house with a bit of warmth and moisture. Under the microscope, strands of their shaggy, bi-coloured hair were encrusted with minute, glimmering granules. Overnight, they conveniently produced some spores. It took awhile, and some dead ends, but eventually I found their name—Calathella eruciformis (thanks, Mycoquebec!). I'm not sure where this particular species fits into the cyphelloid phylogenetic tree since members of its genus appear to be all over the place (see phylogenetic diagrams in Bodensteiner paper cited below).

Calathella eruciformis often grow on dead poplars in loose groups. 

Spores and encrusted hairs of Calathella eruciformis.

Stigmatolemma/Resupinatus

I collected another cyphelloid, a Stigmatolemma/Resupinatus species, during the Alderville Black Oak Savannah Bioblitz. Its cups were so incredibly tiny I wouldn't have noticed them if I hadn't already been magnifying some nearby, relatively gigantic, Orbilia on a rotting log. Molecular evidence supports the suggestion that these cyphelloids are closely related to gilled members of the genus Resupinatus. The immature "cups" growing in-between more mature fruiting bodies of the gilled Resupinatus below certainly look a lot like the tiny characters I found.

The biggest of these Stigmatolemma/Resupinatus cups was .2 millimetres wide.

Before their gills develop, immature Resupinatus sp.
look similar to Stigmatolemma cups.

Flagelloscypha minutissima

Conveniently, since I was already writing this post, I found yet another cyphelloid a few days ago. As usual, when I first looked at it, I was tricked once again into thinking that I'd found an ascomycete—a cluster of immature Lachnum virgineum to be specific, which I've come across several times this season. 

Like Lachnum virgineum, these were tiny, hairy white cups, but since they seemed a tad too small, and there was no sign of a stem on any of them, I stuck a couple under the microscope. Instead of the asci and ascospores I expected to see, there were basidia and basidiospores. There were also elaborately encrusted hairs with delicate, naked whips on the ends, characteristic of Flagelloscypha minutissima, a cyphelloid in the Nia clade.        

The cyphelloid basidiomycete, Flagelloscypha minutissima,
produces minute, stemless, hairy white cups.

Lachnum virgineum, an ascomycete, looks similar to 
F. minutissima, but is considerably larger. 

The encrusted exterior hairs of Flagelloscypha minutisimma
have slender whip-like tips.

Cyphelloid Fungi: What to Look For 

• Hair – a lot of cyphelloids have hairy, often shaggy exteriors
• Size – most cyphelloid fungi are really tiny—less than half a millimetre
• Orientation – cyphelloids are usually down-hanging so their spores, which are not ejected in the same way that ascospores are, can fall out of the cup, tube or goblet
• Microscopy – among other anatomical differences, cyphelloid fungi have basidia instead of asci

References: 

Manfred Binder, et al. (2001) Phylogenetic relationships of the marine gasteromycete Nia vibrissa, Mycologia, 93 (4), pp. 679-688

Bodensteiner P. et al. (2004). Phylogenetic relationships of cyphelloid homobasidiomycetes. Molecular Phylogenetics and Evolution 33 (2): 501-15.

Moncalvo, J. M., et al. (2002). One hundred and seventeen clades of euagarics. Molecular Phylogenetics and Evolution 23: 357–400

J. Breitenbach, F. Kränzlin, Fungi of Switzerland, Vol. 2: Non-gilled Fungi, Vertag Mykologia, 1986 (which conveniently showcases a crew of ascomycetes-like cyphelloid fungi in a group)

Cyphelloid fungi