Red List of Yugra: Pluteus fenzlii

There certainly are many brightly-colored fungi out there, but if you want YELLOW, go for Pluteus fenzlii.

Pluteus fenzlii (Schulzer) Corriol & P.-A. Moreau 2007 is a rather unusual representative of the genus Pluteus.  It is a strikingly yellow agaric that grows on decaying wood of deciduous trees. It is probably widely distributed, but finds are very rare. In Russia, it’s known from several finds in Central Europe and Siberia.

Pluteus fenzlii in Akademgorodok

Speaking of its taxonomy, it used to belong to the poorly known sister genus in the family Pluteaceae, Chamaeota, which includes several rare species of annulate pluteoid fungi (i.e. they look more or less like regular Plutei but have a ring on the stipe). To my knowledge, there have not been any comprehensive studies yet to investigate the relationship between Pluteus and Chamaeota, and it’s possible that there is no distinct borderline between the two genera phylogenetically. A very similar mushroom, Pluteus mamillatus from North America, is also a former Chamaeota (Ch. sphaerospora).

The renaming of Chamaeota fenzlii to Pluteus fenzlii is actually a funny story, because it was done independently by two teams of researchers who published their results within a week, which caused a small fuss reflected in a 2007 article in Czech Mycology.

Elena says Pluteus fenzlii is relatively common in Yugra and collected almost every season. Nadezhda Kudashova, a mycologist from Tomsk, also found it a couple of times and kindly loaned us fragments of her collections as well as a piece of Pluteus fenzlii collected in Krasnoyarsk by one of the most devoted field mycologists in Siberia, Natalya Kutafyeva. I collected it in Akademgorodok in 2012 in a relatively untouched native old birch forest which is part of the Central Siberian Botanical Garden.

Fruitbodies are relatively robust (for a Pluteus); pileus up to 6 cm in diameter, convex to planoconvex, coarsely fibrillose-tomentose, or made up of appressed flocculose squamules, creating a texture very similar to that of the straw paddy mushroom, Volvariella bombycina, and brilliant yellow; lamellae crowded, free, ventricose, whitish, usually with bright yellow edges; stipe 6-8 cm tall, 5-9 mm in diameter, with a small yellow fibrillose ring in the middle or in the lower portion, stipe surface longitudally fibrillose, yellow with paler yellow context showing inbetween fibrils.

Microscopically, the pileipellis is a trichoderm (literally “hairy skin”) composed of palicaded (i.e. arranged in a tile-like fashion, or appressed) hyphae with slightly inflated terminal elements (tips), with bright yellow intracellular pigment. The stipe surface and annulus are made up of similar elements.

Stipe surface hyphae

Cheilocystidia very crowded, mostly bluntly fusiform, arising from the lamella trama, bright yellow.

Pleurocystidia colorless, fusiform or fusiform-ventricose, also arising from the trama, often mucronate (with small round tips) or occasionally with small, finger-like or tentacle-like projections from the area around the apex (especially in Tomsk collections). This is an unusual feature which is rarely observed in another yellow pluteus, the Lion Shield (Pluteus leoninus).

Spores are very rounded for a Pluteus (subglobose to broadly ellipsoid).

spores

Elena found a curious article by Alfredo Vizzini and Enrico Ercole about what appears to be another related species – an annulate form of Pluteus aurantiorugosus. This small species is often confused with Pluteus chrysophaeus, another small yellow species, but specimens described in the paper seem to have the same annulus-like structure as P. fenzlii.

ressaure

Inocybe reisneri Velen. 1920 is another addition to the list of Inocybe section Rimosae from Novosibirsk Akademgorodok. Last August these fibercaps fruited all over Akademgorodok, always near birch (Betula pendula), preferring shaded lawns bordering forest patches, and sides of busy forest trails (Akademgorodok is all about forest trails).Once again, I failed to take decent in situ photos, probably because these fungi were so abundant I kept hoping to find a better-looking group, and fell victim to perfectionism multiplied by absent-mindedness.

Inocybe reisneri. The violet tinge is especially apparent in young fruitbodies

They stand out of the Inocybe crowd thanks to their elegant fruitbodies with subbulbous stipe, shiny silky caps with scattered patches of white velipellis, violet tinge in the upper part of the stipe and in lamellae, and peculiar smell, which I could only describe as fresh and reminiscent of shieldbugs at the same time. The smell was what prevented me from identifying the species quickly, because it required a two-step move: the thing is, the closest species in Funga Nordica and in Kuyper’s 1986 monograph is Inocybe quietiodor, which is very, very similar (apart from the violet tinge), but a key feature in identifying it is its odor, which is said to be the same as “that of Lactarius quietus“. Apparently, Lactarius quietus is a very common milk cap in Europe, and every decent mycologist should know the smell very well. The problem is, it’s mycorrhizal with oak, and there are only a few planted oak trees in Akademgorodok, and no Lactarius quietus under them (at least yet). We had to google up what Lactarius quietus smells like, and learned that it smelled of “shieldbugs and wet laundry“. Bingo! But the violet tinge wasn’t mentioned in any of the sources.

Yesterday, having travelled for over a month and a half, a great book, an English translation of Stangl’s The Genus Inocybe in Bavaria (available from Summerfield Books), finally made it to Ugut (parcels sent to Russia often deserve their own versions of “The Incredible Journey”). I found our mystery species right away just by flipping through color plates, and it was Inocybe reisneri. A reminder of how important a good library is.

Spores

Spores measure  (9.3-) 9.5 – 12.2 (-12.7) x 5.7 – 7.1 (-7.4), L = 9.88,  W = 6.26, Q = 1.58 (n = 92), which makes them a bit larger than what’s given in Stangl’s description.

Cheilocystidia are mostly clavate (not very narrow, not very broad). Pileipellis is comprised of relatively thin, barely inflated hyphae with a delicate zebroid pattern of golden-brown pigment incrustation (there is intracellular pigment as well).

Cheilocystidia

Above the pileipellis there is a layer of interwoven, thin, colorless, collapsed hyphae – the velipellis. There are quite a few branching, anastomosing refractive hyphae (also called vascular, or oleiferous hyphae) – as I’ve already remarked, the abundance of these hyphae in a fruitbody is probably linked to the intensity of its smell. The stipe surface is almost polished with just a few scattered small fibrils of velar hyphae with uninflated, cylindric terminal elements.

Cross-section of pileipellis showing velipellis and refractive hyphae

Red List of Yugra: Arrhenia peltigerina

In the end of 2011, the Department of Natural Resources signed off on the development of the new edition of the Red List of Khanty-Mansi Autonomous Region (a.k.a. Yugra), a document that contains listings and descriptions of rare and endangered species of the area and states measures to ensure their protection.

Elena and I were invited to the workgroup on fungi: we were to decide which (known) species deserved the special protection status, justify our choice and create proper descriptions, images, and distribution maps. The story deserves a separate post (eventually… someday).

We planned several fieldwork events for 2012 for the workgroup in order to extend our knowledge of the mycobiota of the region. I know this may sound perplexing to a “civilized” mycologist (amateur or professional), but in Russia the mycologists per square km ratio is such that even several weeks of thorough surveying do make a huge difference. To illustrate,  there are currently less than 10 active field mycologists in Krasnoyarsk region (way less), and the area of this region is almost two and a half million square kilometers. Things aren’t any better in Yugra, much of which is unpopulated impenetrable taiga and peatlands.
But, as usual, things went their own way, and ultimately the big plan boiled down to just two – spontaneous – expeditions. The first one, in the end of July, was a disaster – albeit an exciting one (we joined a team of firefighters had to flee from a forest fire). In September, I joined Elena and one of the reserve’s rangers in what’s called учеты боровой дичи (something like upland fowl route survey, to monitor populatons of various grouse species). We were air landed to a remote ranger house on the southwest corner of the nature reserve territory, aptly named Medvezhiy Ugol (Bear’s Corner, a Russian expression meaning a remote spot, wilderness, boondocks, …). 

Territorially, Medvezhiy Ugol (click to see map) is located in the geobotanical province know as south taiga, in a densely forested, highly bogged area where several important rivers of Western Siberia originate as a network of small winding rivulets.

On the way to the ranger house

Interesting finds began on the way from the H-pad: while dragging my backpack to the house, I found a weathered Limacella illinita var. rubescens, a peculiar, slimy, and rare relative of the Fly Agaric; on a pile of old logs left after the building of the house we found several bright orange-yellow fruitbodies of Ophiocordyceps cf. corallomyces, a fungus which kills and eats fly pupae buried in rotting wood; several days later we came across a rare peatbog coral fungus, Clavaria sphagnicola – to name a few.

Medvezhiy Ugol ranger house of the Yuganskiy nature reserve

We spent a blissful two weeks hiking, collecting and determining. We came there shortly after the diversity peak of late August and early September, nevertheless we recorded 221 species, 44 of them were first-time collections for Yugra.

One of the most interesting finds was one of the least colorful of all.  In fact, we failed to notice it for days even though it grew virtually on our doorstep.

Arrhenia peltigerina (Peck) Redhead, Lutzoni, Moncalvo & Vilgalys 2002 is one of the few fleshy fungi which are of interest both to mycologists and to lichenologists. It is a small, brownish-gray (or grayish-brown) and overall inconspicuous agaric that’s remarkable in that it grows on thalli of big, leafy lichens of the genus Peltigera, a.k.a. dog lichens; their relationship is most likely parasitic. There is little information available on this species. It is said to be widely distributed, but probably often overlooked or just rarely forms fruitbodies even where its mycelium is present.

The thing is, most lichens are extremely sensitive to environmental pollution; they thrive only in very clean places (for example, there are virtually no lichens in the center of Novokuznetsk, a city famous for its metallurgic plants). It’s possible that A. peltigerina needs good, well-fed, and healthy Peltigera in order to produce fruitbodies. The forest around Medvezhiy Ugol is full of all sorts of lichens: from gorgeous “tree hair” such as Ramalina, Evernia and Bryonia  to bright patchy lichens on tree bark and fallen trees. The latter were often carpeted with large colonies of Peltigera spp. We noticed that some of these colonies were discolored in a peculiar way, with white spots on green leafy thalli resembling patterns on leaves of variegated forms of cultivated plants. Eventually we found that often where there was discoloration, there were also small, grayish, Omphalina-like fungi – I guess it took us so long because numerous brighter wood-inhabiting mushrooms (Pluteus, Tubaria, Galerina, etc.) nearby effectively drew our attention from their modest comrades. It took us a while to see the connection 🙂

Arrhenia peltigerina. Note the discoloration of the lichen. The brown fungi on the left are either Galerina marginata or Kuehneromyces vernalis.

Over the next few days, we found numerous colonies (infestations?) of Arrhenia peltigerina by looking for discolorations on Peltigera pads. The mushroom seems to prefer large, moist colonies of Peltigera growing on large, well-decayed fallen trunks of aspen (Populus tremula). Shame on us, but we still haven’t found out the exact identity of the Peltigera they grew with.

We collected several specimens and from now on we’ll be looking for this species in other places.

You may wonder – why give such an obscure species special protection status? The answer lies in its ecology: since it’s obviously not very commmon, and thrives where there are very healthy lichens, and healthy lichens thrive in clean environment, protecting this species means protecting these pristine, unpolluted spots, which are becoming more and more rare in Yugra, as the (mostly state-owned) oil and gas industry falls all over itself to pump out and export as much carbohydrates as possible as quickly as possible at any price (at this point I’m tempted to whine about what Rosneft does to the land around Ugut, but it’s a separate story)….

New finds in 2013. 3 – Inocybe sp. (sect. Rimosae)

I’ve already mentioned that Akademgorodok is home to all sorts of species of the genus Inocybe, which seem to enjoy human company: many of them show a marked preference for alleys, courtyards, old playgrounds, trails, or grow under small patches of trees between residential houses.

Many of these (sub)urban Inocybes belong to the section Rimosae, which is characterized by fibrillose-rimose (radially split) caps, smooth, amygdaloid to ellipsoid-ovoid spores, lack of thick-walled, crystal-bearing cystidia (metuloids) and dense rows of thin-walled, clavate (club-shaped) to cylindric cheilocystidia along lamella edges which look like whitish “frosting” under lens. Unfortunately, way too often that’s nearly as far as you can get with identifying species of this section, because even microscopic differences are often subtle; it’s hard to be objective about some of the key features; other are evanescent or hard to put into words (such as the strength and unpleasantness of smell, degree of light-brownness and non-yellowness, scarcity of tiny patches of cottony hyphae = velar remnants, and so on).

Despite these deterring complexities I decided to study and sort out the big pile of specimens that’s accumulated over the past few years, including about 20 more or less decently recorded specimens collected last August. Upon initial examination, many of them fail to fit into the available keys seamlessly: a feature or two always stands out.  My plan now is to to measure spores and cheilocystidia, look at stipe and pileus surfaces of all specimens, take notes on gross morphology, then to sum it up in tables and see if any patterns and correspondencies emerge.

Meanwhile I’m just enjoying their grayish-brownness.

Here is a curious one. It was a common sight in late summer on areas of dry, semi-barren, compressed soil, such as abandoned lawns, sides of park trails, etc.

It keys out half-heartedly as Inocybe perlata (using the key to the section provided in a 2009 article by Ellen Larsson et al.) based on its robust habit, spore shape and size, and lack of yellow shades in its coloring, but one thing doesn’t fit: fresh fruitbodies had a faint earthy-spermatic smell, but a very strong and surprising smell appeared when I soaked a tiny piece of dry specimen in water. I ended up running around the nature reserve HQ with pincers:  – “Here, smell an Inocybe!” – “Ugh, no way!” – “Smell it!” – “Why… well ok…. Cool! Honey!”. The consensus was, the smell was not even real honey-like, but stronger and clearer, rather like cheap artificial honey flavoring.

I’m not sure whether the slight brownish discoloring seen on some parts of the fruitbody is taxonomically relevant.

There are two species in the aforementioned 2009 article that are said to smell like honey – one is Inocybe cookei, which our mushroom is definitely not, and the other is an Inocybe melliolens, described from France. I haven’t found a detailed description of the latter yet, but Google shows images of very similar-looking fungi, e.g. here or here. There is even what looks like thin velar remnants on pileus surface in the second photo, and I also found what appears to be velipellis fragments on the surface of one of the fruitbodies.

However, these fungi seem to have broader (clavate, not cylindric/subcapitate) cheilocystidia (up to 22 μm wide), although I’m not sure that this feature is stable enough to mean much (if it does, then Inocybe maculata appears in the picture).

There are abundant refractive hyphae found throughout the fruitbody, which in my experience correlates directly with smell strength. Here’s a picture of such refractive hyphae in the pileipellis:

The caulocystidioid elements on the stipe (they’re the whitish fuzz) are very typical for species of this section:

Here’s the pileipellis, with rather wide, inflated hyphae:

and the velipellis:

Spores

I guess the only way to get a definitive answer is molecular study: hopefully one day an Inocybe expert becomes interested in Siberian samples….

New finds in 2013. 2 – Clavulinopsis subarctica

Clavulinopsis subarctica (Pilát) Jülich 1985 is a rare fungus which is occasionally found among Sphagna in raised bogs. It’s one of the very few clavarioid fungi (along with Clavaria sphagnicola) that grow in the demanding conditions of this biogeocoenosis. Indeed, I was surprised to find a coral fungus in the middle of a wet, sparsely treed peatbog west of the Kinyamiskoye lake near Ugut, and I doubt I’d ever find out what it was without help from a true expert in wetland fungi, Nina Filippova (check out her amazing flickr album).

You can read about this species (as Ramariopsis subarctica) in a 2012 Czech Mycology article by Martina Vasutova. As far as I know, it’s been collected in Yugra on one occasion, but, just like Ascocoryne turficola, it’s so rarely found mostly because it grows in nearly inaccessible spots very few mushroom enthusiasts would visit voluntarily 🙂