Unveiling the Veiled Polypore: Cryptoporus volvatus

I spent an hour this morning carefully destroying fifteen veiled polypores—totally ripped them apart. Odd thing to do? Nope, not in my neck of the woods.

Cryptoporus volvatus produces acorn- to walnut-sized cream-coloured bubbles on the bark of recently dead and usually still standing conifers. Sometimes it also appears on living trees. 

C. volvatus grows on recently dead or dying conifers.

At first glance, these cute little polypores might be mistaken for small, wood-inhabiting puffballs, or even the immature fruiting bodies of the slime molds Reticularia lycoperdon or Lycogala reticularia.

Cryptoporus volvatus can superficially resemble (left to right)
Lycoperdon pyriforme puffballs (Wikipedia), or immature slime
molds such as Lycogala flavofuscum and Reticularia lycoperdon.

The reason they might not be immediately identifiable as polypores is that their pore surface is hidden, hence the "crypto" part of their name. Unlike other polypores, the spore-producing bottom side of the "veiled polypore" is covered by a volva-like flap of tissue—a covering that would apparently prevent the free movement of spores.  

Note both the newly formed openings, or ostioles, and the
shedding of the lacquer-like coating (Dan Molter)

So how do these diminutive polypores manage to get their spores out into the larger world? For many years it was assumed that insects and other arthropods that are known to spend time inside these fungi are the obvious vector for spore dispersal. C. volvatus even provides a convenient doorway to gain access: a small ostiole that forms at the juncture with the tree, which enlarges as the spores mature. 

The opening at the top of the photo is the ostiole that forms
in the pore covering. The other holes were made by insects.

But a 1980 study cast doubt on the insect link. The paper, published in Mycologia, posited that spore dispersal was primarily via air movement, just as it is for other polypores. The authors came to this conclusion by rigging up a bunch of C. volvatus with spore-collecting contraptions, then suspended the collected  spores evenly in a liquid, and finally counted them using a hemocytometer, a gauge invented in the 19th century for blood cells. And they found a lot of escaped spores—an average of 2.5 billion per basidiocarp. That's a lot of spores sent on their way by wind—comparable, in fact, to other polypores. 

So why evolve a covered pore surface in the first place? The authors suggest that it has to do with moisture retention. Many polypores are capable of resuming sporulation after they have completely dried out when they are rehydrated by rain. Not the short-lived C. volvatus, which usually grows well above the ground on standing trees where it is open to the desiccating effects of sun and wind. Basically, it's got only one chance to produce spores, so a protective tube covering makes sense. 

The lacquer-like coating that covers young C. volvatus

is also thought to help retain moisture.

But that air-movement and spore dispersal study didn't make the people who had a gut feeling that insects still belonged in the equation go away. Nope. This isn't surprising considering the number and variety of mini spelunkers that choose to hang out in dark, spore-covered, Crytoporus caves. 

Insects, like this one with metallic red elytra, tuck themselves
tightly into the corners when you remove the covering.

One Japanese study that looked at 438 separate C. volvatus basidiocarps counted a total of 8,990 individuals, insects that belonged to 17 different species, including 4 specialists that prefer C. volvatus over everything else. Some of these little mycophagists munch on the tubes, some eat the flesh, while others focus on the fallen spores. Predators enter as well. Several studies around the world have focussed on these insects and the possibility of their being a necessary vector for spore dispersal. 

This sporocarp has been completely hollowed out by insects.

In one Korean study, beetles were collected from C. volvatus basidiocarps and then "vortexed" (what a great verb!) in ethanol to dislodge any spores that were attached to them. Again, a hemocytometer was used to count the spores each insect specimen carried. And they carried a lot: from 10,000 to half a billion. That's a lot of spores to be moving around for no good reason. 

Basidiocarps of C. volvatus actually grow out of exit, entrance, and ventilation holes made by bark beetles—bark beetles that kill conifers but that are not known to feed on the fruitbodies of C. volvatus. So how do the spores gain entry to a tree? Air movement can't be enough. But it turns out that at least one species in the Korean study that feeds/breed inside the volval chambers of C. volvatus also spends time under the bark of dead conifers, so it could easily be a vector for spore transfer, perhaps to a passing bark beetle. 

My grand haul of Cryptoporus volvatus critters,
minus a bunch of tiny larvae.

I found this attractive, metallic beetle inside a
Cryptoporus volvatus "cave." Can anyone name it?

This guy was similar to, but a lot smaller than 
beetles I regularly find on Pleurotus species. 

References:

T. C. Harrington, Release of Airborne Basidiospores from the Pouch Fungus, Cryptoporus volvatus, Mycologia, Vol. 72, No. 5 (Sep. - Oct., 1980), pp. 926-936

Kohmei Kadowaki, Species coexistence patterns in a mycophagous insect community inhabiting the wood-decaying bracket fungus Cryptoporus volvatus (Polyporaceae: Basidiomycota), Eur. J. Entomol. 107: 89–99, 2010

Myung Soo Park, et al., Determination of coleopteran insects associated with spore dispersal of Cryptoporus volvatus (Polyporaceae: Basidiomycota) in Korea, Journal of Asia-Pacific Entomology 17 (2014) 647–651

C. volvatus on E-Flora BC

When Is Fuligo septica Purple? Not Very Often!

I was out with Ruby last summer when I spotted an unusual patch of colour in the distance, a pale, pretty, pinkish violet perched atop a moss-covered oak log. As Ruby and I got closer, it became obvious that it was not a wayward bit of plastic or a spent balloon, it was something special.

Ruby with Daedaleopsis confragosa
and Hypoxylon fragiforme

Now, Ruby is a fabulous foray companion — not only does she make me laugh, I can also count on her to give me warning of approaching wildlife, such as bears, when I’m silently concentrating on fungal marvels. Now that she’s outgrown her jubilant puppy habit of pouncing directly on top of whatever exciting specimen I happen to be focusing my camera on, she is almost perfect.

Ruby is a log-walker.

Almost, but not quite. Her one remaining flaw (besides, like most dogs, occasionally rolling in something nasty - see my last post), is that she is a log-walker. There’s nothing Ruby loves more than to scramble up onto a fallen tree and elegantly walk it from one end to the other, as sure-footed as a balance-beam gymnast — a problem if I’m trying to photograph or collect a specimen from said log.

I knew I had to distract her, so I gathered a few sticks and began throwing them until I reached my quarry. What I found was a large patch of not-quite-set, but fully-formedslime mold, Fuligo septica, but a F. septica that was, of all things, a beautiful lavender instead of bright or dull yellowish.

Immature violet Fuligo septica 

I managed to keep Ruby at bay long enough to collect a sample and took it home. I set it aside to mature and produce spores and started reading. I took more pictures. I looked at under the microscope. I read some more.

Immature violet Fuligo septica showing pale pink plasmodium 

I found a reference to a F. violacea, (Persoon, C.H. 1801. Synopsis methodica fungorum), but little information about it other than the original Latin description which refers to a yellow outer shell. Mycobank clumps F. violacea together with numerous other synonyms of F. septica.  

Violet Fuligo septica two days later

Having reached the limit of what I could find on line, I sent photos to Michael Warnock, one of the myxomycete aficionados of my local club, the Mycological Society of Toronto.  Michael replied with the suggestion that my specimen might be a F. septica that had been attacked by the myxomycophagist (slime mold eater), Nectriopsis violacea. I’ve actually found this curious character before. It looks completely different than what I’d found.

Nectriopsis violacea, an ascomycete, feeds on Fuligo septica.

The perithecia of Nectriopsis violacea are royal purple when moist.

N. violacea is an ascomycete that specifically targets F. septica. It’s not terribly common — I’ve only seen it twice, both times at the Cain Foray near Algonquin Park in Ontario — but it’s unmistakable. Its colour ranges from dark purple to purplish white (not pinkish lavender), peppered with minute darker pimples, the perithecia through which its spores are released. Not what I had found.

A squash-mounted perithecium of Nectriopsis violacea 
along with globose spores of Fuligo septica

F. septica, known for centuries as Flowers of Tan because of its proclivity to colonize the piles of tannin-filled wood chips used in the leather tanning industry, has several commonly found forms. The dull beige version that can sometimes produce massive fruitings on hay or straw or compost piles has been fondly called Dog Vomit Slime (self-explanatory). In Scandinavian folklore, it's identified as the vomit of troll cats, a creature I want to see. 
In my neck of the woods, I more often encounter a yellower, more compact version that matures from sometimes startlingly yellow, huge masses of plasmodium, a stage that gave rise to another descriptive moniker, Scrambled Egg Slime. This plasmodium sometimes matures into large, dull-yellowish amorphic patches on logs and trunks of trees. Other times it separates into much smaller, individual, deep cadmium yellow pillows. All of the above forms contain dark purplish brown masses of globose, minutely spiny spores that all look the same microscopically. None of these forms are pinkish violet. Not even close. But I did read that the final colour can have a connection to the acidity of the substrate on which its aethalia (pillow-shaped fruiting bodies) have chosen to form.

A metre-wide patch of Fuligo septica plasmodium,
also known as Flowers of Tan

Under the microscope, I found another anomaly — the spores of mine all contained oil droplets of various sizes. So did I actually have a different species? Or did my sample have some kind of weird infection?

Spores of violet Fuligo septica showing oil droplets

I found an old paper describing techniques for propagating F. septica and decided — in my completely amateur way — to try to grow mine. I put some spores on a sprinkling of ground-up oatmeal on a damp coffee filter in a covered container. Within a couple of days, the spores produced a flash of pigmented growth. The first day it was a bright, deep fuchsia, which then settled down to more of a pale pink, like the interior of the original immature aethalia. My experiment then stagnated and did nothing until it began to smell. I threw it out.

My spore-growing experiment produced brief pigmented growth.

Still, there had been no sign of the usual bright yellow pigment that F. septica commonly produces, so what did I have? I decided to go to the top of the myxomycete food chain and emailed Frederick W. Spiegel at the University of Arkansas, a specialist in Mycetozoans, a grouping of slime molds that include the genus Fuligo. He, in turn, forwarded my message and photos to his colleague, Steven L. Stephenson, author of numerous publications, including the indispensable Myxomycetes: A Handbook of Slime Molds, noting that Steven had likely seen more F. septica fruitings than any other human being.

Normal egg-yolk yellow Fuligo septica plasmodium

Steven, at first unable to open my image files, suggested once again that I had a found a F. septica specimen that was being consumed by N. violacea. Once he was actually able to see my photos, though, he informed me that he had once come across F. septica approaching the colour of mine, possibly in Alaska. He also said that oil droplets and other inclusions are found in a lot of myxos. His final word was that, as F. septica is almost certainly a species complex, what I had found could only be called that until such time that someone decides to make the effort to sequence a series of collections. As per his suggestion, I have frozen my collection for future study. Any takers?


Many thanks to Michael Warnock, Frederick W. Spiegel, and Steven L. Stephenson!

Three stages of a pale yellowish beige Fuligo septica

The colour of Fuligo septica can vary enormously.

References & Resources

Steven L. Stephenson, Myxomycetes : a handbook of slime molds, Timber Press, 1994.

Patricia M. Scholes: Some Observations on the Cultivation, Fruiting and Germination of Fuligo septica, J . Gen. Microbiol. (1961), 29, 137-148 

Tom Volk's entertaining Fuligo septica page

Some fun Fuligo septica history from Historical and Literary Botany: Containing the Qualities, Anecdotes, and supperstitions, relative to trees, plants, and flowers, which are mentioned in sacred and profane history - Volume 3 By Eliza P. Reid 1826 

Great series of photos from Wayne’s World of the different stages of pale version of F. septica plasmodium growing on wood chip mulch

The Myxomyceticolous Species of Nectria: Gary J. Samuels Source: Mycologia, Vol. 65, No. 2 (Mar. - Apr., 1973), pp. 401-420

An amazing BLUE Fuligo!!!
 

A Silver Lining to a Dog Owner’s Nightmare: Microstoma protractum

Serendipity 

serənˈdipədē

Noun: the occurrence and development of events by chance in a happy or beneficial way

My good friend, (who shall remain nameless so as not to further embarrass her), joined me for a walk in a forest a fifteen minute drive away. As always, I brought along my dog Ruby, and my friend brought along her dog — Ruby’s best buddy, Fritz. My friend offered me her plasticized “dog hammock” to cover the backseat of my car, but I poo-pooed the need for such protection. It had been dry, so I didn’t expect the dogs to get into the black smelly muck that is more easily found later in the year. Really, what could happen? 

Best buddies, Fritz (left) and Ruby (right)

Though it was a gloriously warm day, here in central Ontario it was still a few weeks too early for morels and there was still the odd patch of snow lurking beneath brush piles. Normally in early spring I have no trouble finding all kinds of interesting fungal surprises that have overwintered but, since it hadn’t rained in a week, such things as jellies and crusts and delicate cups that swell when wet, had shrivelled into invisibility. It was such a beautiful day, though, that I was happy enough to simply take pleasure in the company of my friend and the gleeful antics of our dogs racing between the trees.

A few early spring finds (from top to bottom, left to right):
Encoelia fascicularis; Merismodes sp.; Stictis radiata; Arachnopeziza aurata;
Tremella mesenterica feeding on Peniophora incarnata; and Exidia recisa.

We were nearing our turnaround point when, for a moment, we lost sight of Fritz. But then we saw him. What was he doing? Oh, dear…he was rolling in something. (If the reader has never been a dog owner, or is particularly squeamish, he/she may wish to skip down to *)

“S…t,” we both said simultaneously. 

Ruby's a cougar

Now anyone who owns a dog is likely to be familiar with this vile scenario. Be it the putrid remains of a dead animal, greasy raccoon scat, or a freshly dropped cow patty, nothing makes some dogs happier than rolling in such nastiness, usually in an anatomically deliberate way, specifically focused on grinding the offensive matter all around the neck, ears, and collar. Which is all fine and good when you’re near home and have a hose ready. It is not fine and good when you need to get home in a car, particularly a car that does not have a dog hammock protecting the backseat.

Even ten feet away from Fritz we could smell it. It was, indeed, feces. A lot of feces, smeared all through the dog’s long, silky fur.

My friend, knowing that it was unlikely that I was going to let Fritz into my car in this state, first comically tried to clean him in a vernal pond using fistfuls of last year's leaves that I handed her—a valiant attempt, but completely ineffective. In fact, the wetting and smearing of the foul substance only worsened the smell.

Both dogs love mushrooming. Fritz can be a bit of a goof!

Fortuitously, there was a river not far away and, equally fortuitously, some rags and a towel we could retrieve from the car on the way, so we headed in that direction, both my friend and I trying to keep upwind of the dog as we walked. The stench was so unbelievable it was laughable. At least, I thought it was laughable; it wasn’t my dog who had to be cleaned.

When we finally got to a shallow area at the “delta” of a spring creek running into the river, which was racing high with melt water, my friend rolled up her pant legs and waded in, dragging Fritz along with her. While Fritz was being dunked and vigorously scrubbed, Ruby splashed back and forth on the muddy shore, barking like mad to express her solidarity with her friend during his worrisome ordeal.  

*A "Good" Find

My friend finally released the newly car-worthy Fritz. Trailing streams of water from his sopping coat, he bounded directly towards me and Ruby. That, of course, was the exact instant that I spotted two little red nubbins poking out of the mud between Ruby's still dancing feet. I’m not quite sure how I managed to scoop them up before they could be either crushed or buried by a dog paw, but I did. I was now, however, a little wet since Fritz, who'd not yet had a chance to shake, managed to collide with me like a wet mop.

The cups of my Microstoma protractum were small,
but they can be up to 2 cm. wide

On closer examination, there were actually three nubbins, two of which were clearly cups. I carefully rinsed the mud and sand off them in the river. Oddly, they had very tough stems that looked as if they had rooted in the mud. I had no idea what I'd found, but I immediately declared to my friend that it was a "good" find.

"...that you would never have found if Fritz hadn't rolled in that s...t!" she said, delighted to be so easily exonerated for her dog's instinctual behaviour.

See? Serendipity.

Microstoma protractum

Once I got my find home and visually keyed it out in Ascomycete Fungi of North America (Beug, Bessette, Bessette), they were easily identifiable as Microstoma protractum (sometimes called M. protracta, an unnecessary feminization of the species name since the root "stoma" is sexless). 

Rinsed and dried, my M. protractum had dense,
felted hairs the full length of its pseudorhiza.

A hair-rimmed pore eventually opens into a torn-edged cup (with dog hair).

They're fascinating little characters, both macroscopically and microscopically. Apparently, had I not been in such a hurry to pluck them from the danger of prancing dog paws, I could have followed each tough little stem, or pseudorhiza, (a rootlike subterranean elongation of a stem), to a "mother" pseudorhiza growing from a buried piece of rotting wood. This perennial "mother" can give rise to aerial stalks each year, producing more and more cups from one year to the next. It is no wonder that so many common names in other languages refer in some way to this fungus being like a tulip: dense older colonies of M. protractum look impressively like beds of tulips. 

In German, M. protractum is called Eingerissener Tulpenbecher, or "torn tulip cup."   

M. protractum is a northern latitudes/montane species from the Sarcoscyphaceae family,  occurring in Europe, Japan, Russia, and North America. It has been found only twice in Great Britain, in Scotland, first in 1890, and then exactly 20 years later in the same location and is now likely extinct. It is also rare enough in Poland to be a protected species. Its sibling, M. floccosum, is much more common, much hairier around the rim, and does not usually grow from buried wood.

The dichotomously branched paraphyses contain plentiful pigment granules.

Microscopically it's startlingly colourful due the plentiful amounts of pigment found in its dichotomously branched paraphyses, granules that turn green in Meltzer's. The spores are large, elliptic-fusoid (25-50 x 10-16µm), usually with one large oil droplet and several smaller ones. 

M. protractum spores range in size from 25-50 µm long.

The asci have squiggly "tails."

The long asci (200-275 x 20-23 µm) are particularly interesting. Not only do they have quite lovely squiggly tails, they also each have a very cool operculum (lid that opens to release the spores) that, instead of being apical, opens to the side, which makes the empty asci look like eyeless sea creatures with their mouths open.  

The asci have strangely lateral operculi (lids that open to release their spores). 

The only thing disappointing about this fabulous little asco was that — being forced to prematurely pluck them — I did not get any pictures of them in situ. Though these lovely little red cups are, indeed, often found in moist areas just after the snow melts, I have not been able to find any reference to their growing while submerged under water, which mine must have done — the mud they had erupted from had clearly been very recently under water (earlier that day? the day before?), probably for a duration of at least several weeks while the snow was melting, and the two that were mature enough to open were packed with mud. It would have been nice to have a record of them growing in this peculiar habitat.

So I went back to see if there were more that I had missed. Though there was nothing to find in the mud beside the water in the spot I'd found the first ones, tucked behind a log a few meters away and a few feet up from the water, I found another patch — not exactly a bouquet, but enough for some photos!

Update

I went back four days after I found the second batch and found another poking out of the original spot. Here's a picture:

References

Ascomycete Fungi of North America: a mushroom reference guide. By. Michael W . Beug, Alan E. Bessette, and Arleen R. Bessette. 2014. Austin: University of Texas Press

Spinner, B. The Larger Cup Fungi in Britain, Field Mycology Volume 1(4), October 2000

Microstoma protractum on Funghi in Italia 

Microstoma protractum on Mycoquebec