Rust on Rosa

Spotted this on some kind of wild Rosa sp. in the car park at work.

The undersides of the leaves are covered in an orange rust, with fuzzy black patches.

Zoom in and those black patches look like this, kinda bushy!

Those black 'bushes' are clumps of teliospores that look like this:

Teliospore mounted in water. 100x magnification.

I reckon what I've got here is Phragmidium tuberculatum. The narrow pointy bit on the end (the 'apical papilla') is a distinctive feature of this species, according to Ellis & Ellis's Microfungi on Land Plants.

For the record
Date: 24/06/2018
Location: Woods Mill, Henfield
Grid reference: TQ218138

Record entered into FRDBI 07/09/2018

A very common rust

I joined Rachel Bicker and the Gatwick Greenspace gang at Gatwick Wildlife Day yesterday – in the grounds of the Gatwick Aviation Museum. 

Conditions were fairly dry, so I had drawn a blank in my hunt for fungi until the orange-yellow speckling on the leaves of this Musk Mallow Malva moschata caught my eye. Another rust fungus!

Here it is under the stereomicroscope.

Ellis & Ellis's Microfungi on Land Plants has provided a promising candidate for the identity of this rust: Puccinia malvacearum. Malcolm Storey has some images of this species on bioimages.org.uk which look like a good match. 

Here's what I'm seeing under the microscope.

Teliospores 100x magnification. Mounted in water.

Teliospore 44x magnification. Mounted in water.

This matches the description of Puccinia malvacearum in The British Rust Fungi (1913) so I think I can claim an identification on this. Ellis & Ellis describe it as "very common".

Interestingly, W.B. Grove had this to say about Puccinia malvacearum, back in 1913:

It had first appeared in Europe less than 50 years before and W.B. Grove commented that "the rapidity of its distribution has few or no parallels among plant diseases."

I wonder what changes in distribution we can expect to see in the 'rare' Puccinia commutata which I found the other day...

For the record
Date: 23/06/2018
Location: Gatwick Aviation Museum, Charlwood, Surrey (modern administrative & vice county)
Grid reference: TQ250409

Record entered into FRDBI 07/09/2018

A rare rust?

Tempting to say I found this rust fungus but I think it would be closer to the truth to say it found me. It all but jumped out at me while I was enjoying a cup of tea at the Holywell Tea Chalet.

It was growing on Red Valerian Centranthus ruber. I just recently purchased Ellis & Ellis's Microfungi on Land Plants so I thought I'd try my chances at identifying it.

Ellis & Ellis list just one fungus specific to Centranthus which is Ramularia centranthi. But the description didn't match my collection at all, so I turned to Google. "Rust fungus on Red Valerian" brought up a a discussion thread on www.fungi.org.uk with photographs of something very similar-looking, identified as Puccinia commutata.

I posted my photograph and this tentative identification on the BMS Facebook page and in less than 24 hours my collection had come to the attention of a mycologist specialising in this group of fungi: Nigel Stringer. It seems that Puccinia commutata is relatively new to the UK (there are fewer than 10 records on the FRDBI database, with the first being from 2009) and Nigel is keen to compare my collection against descriptions of the rust species which occur on Red Valerian on the continent.

Nigel advised that I should press my collection in an envelope or between two sheets of paper; so I have found an additional use for Ellis & Ellis as its impressive weightiness makes it ideal for this job! I shall send my collection off to Nigel in a week or so, once it's been successfully pressed, and look forward to having its identification (hopefully) confirmed.

I did have a go at observing its microscopic features myself, comparing against Malcolm Storey's images here (with thanks to the Lost & Found Fungi project for pointing me in the direction of those).

I got a spore print and found these things which look like collapsing, round orange sacs (aecidiospores?). About 4.5 - 5 microns in diameter.

Mature aecidiospores (?) 100x magnification. Mounted in water.

Looking at a cross-section of one of the fruit bodies (the 'aecia', singular = 'acium') I encountered this.

Aecium squash at 100x magnification. Mounted in water.

I thought that mass in the middle might be 'peridial cells'... whatever they are.

Here's those bits at the top left, at higher magnification.

Aecium squash at 400x magnification. Mounted in water.

It's always difficult interpreting the microscopic features of fungi you've never encountered before. So would appreciate any hints as to what I'm looking at here!

Brian Douglas sent me a link to an old publication on The British Rust Fungi which is helpful for understanding the basic biology of these things. But this is very unfamiliar territory for me.

There was also some discussion over on Facebook about how Puccinia commutata differs from Endophyllum centranthi-rubri, as featured on the Plant Parasites of Europe site; and whether there's a case of over-lapping (broad vs. narrow) species concepts here. That's mycology for ya!

UPDATE 18/08/2018

My find at Holywell Tea Chalet came to the attention of Puccinia expert, Nigel Stringer - via the BMS Facebook page. Under instructions from Nigel, I preserved my collection (by pressing it between the pages of one of my weightier ID guides, for a week or so) and posted it off to Wales.

Nigel has been in communication with Brian Spooner about this collection, and notes that it is very difficult to tell Puccinia commutata from Endophyllum centranthi-rubri in the aecial stage (which is what I found). However, Nigel found that the aecial characteristics of my collection  (spore dimensions, peridial cell measurements and the surface cracking of one of the 'faces' of the peridial cells) exactly match the descriptions available for P. commutata. On that basis, he has confirmed it as P. commutata. However, he went on to say that "the clincher would be finding the telial stage on the host from now on. The telial stage would be shiny black blobs mixed in with the yellow coronets ... Visible to the naked eye and may be long and narrow as well."

So folks, if you come across something that looks like this on Red Valerian - look out for some shiny black blobs! I feel a trip back to Holywell Tea Chalet coming on.
 


For the record
Date: 20/06/2018
Location: Holywell, Eastbourne, East Sussex
Grid reference: TV603973

Puccinia commutata confirmed by Nigel Stringer
Record entered into FRDBI 07/09/2018

Fungus records: how are they used?

I gave a presentation to the British Mycological Society's group leaders' meeting in Barnsley at the weekend on Fungus records: how are they used?

I've put my slides & notes together in a Google slide show, in case anyone else is interested.



Happy to discuss!

Something in the night

Well I'm walking 'round Woods Mill, figuring I'll see some bats... Last Saturday night. And I found these lovely mushrooms, popping up on an old fire site.

I figured they were something from that confusing Coprinellus / Coprinopsis / Parasola area of fungal taxonomy. I wouldn't normally attempt to identify such cryptic things but they looked so alluring in the moonlight, I thought I'd give them a go.

Back home I was able to get a closer look at the fruit bodies under the light and got some photos before bed.

That tan nubbin on top, the pleated cap and pale edge to the gills seemed like distinctive features; along with the fact it was growing on an old fire site. I set the cap down on a glass slide to get a spore print over night.

The morning after the night before

Next morning, I found my mushroom had become shadow of its former self. It wasn't deliquescing as such. But it had begun to lose all its structure.

I found a smearing of charcoal coloured spores on the slide, and got them under the microscope.

I measured around 10 spores and made the spore length 12.5 - 13.5 microns, with the average being around 13.0 microns long. Width 5.5 - 6.2 microns, average 5.8 microns.

That seems pretty big for these Coprinellus -type things. Over on the British Mycological Society Facebook page, Richard Shotbolt had suggested perhaps my collection could be Coprinellus impatiens or something very close. But then my measurements seemed a bit on the big side for C. impatiens. (I still have some anxiety about whether I'm actually doing this right but I have checked the calibration on my eyepiece camera at least three times, so I should be doing it right.)

I spent a while poring over descriptions in Funga Nordica, but I'm going to have to admit defeat on this one. I think I'd need to look for microscopic features on the cap ('pileocystidia') to confidently narrow things down but didn't fancy my chances at finding them, as the fruit body was collapsing before my eyes. 

Anyone got any more tips on pinning down an ID for this one? I've still got a little dried out fruit body so could have another go at examining microfeatures, if I knew what I was looking for. 

For the record
Date: 9 June 2018
Location: Woods Mill, Henfield
Grid reference: TQ217136

Almost missed 'em

Came across these mushrooms sprouting up from a bank in Horton Wood on Sunday.

They were pretty fragile and many were broken and toppled over by the time I got to them.

I was intrigued to see they were very similar (the same?) as a mushroom I'd found the day before at Lodsworth (photos here). Interesting how environmental conditions will trigger particular species of fungi to suddenly appear.

I think these are a Psathyrella species.

They produced a reddish brown spore print.

I also had a look at the microcharacters...

Mature spores mounted in water at 400x magnification.

The smooth, dark brown spores were all between 7-8 microns long x 4 - 4.5 microns wide.

Gill edge squash mounted in water at 400x magnification.

I think I could make out a 'germ pore', which is significant in the key in Funga Nordica.

Gill edge squash mounted in water at 400x magnification.

I found lots of 'utriform' cheilocystidia on the gill edges. I looked for cystidia on the gill face (pleurocystidia) and couldn't find any.

An attempt at a gill trama squash mounted in water at 400x magnification.

You can just about make out a basidium here. It looks like it's bearing two spores, but I think I saw at least one more when I was twiddling the focus knob.

There are loads of different Psathyrella species, but I'm hoping these characters together make this a fairly safe bet for Pale Brittlestem P. candolleana  – a common and widespread species found in woodland and grassland.

For the record
Date: 3 June 2018 
Location: Horton Wood, Small Dole
Grid reference: TQ208127 (site centroid) 

Record entered into FRDBI 07/09/2018

Sporulating now

I headed over to Lodsworth today for an introduction to the Ferns of Sussex with Bruce Middleton. Not fungi. But they've got spores so I thought I'd allow them a guest appearance.

Ferns (& their allies) of Lodsworth, from left to right: Wood Horsetail, Bracken, Hart's-tongue Fern, Maidenhair Spleenwort, Rusty-back Fern, Black Spleenwort, Hard Fern, Soft Shield Fern, Scaly Male Fern (if I've remembered them right).

Walking through a meadow, towards the river, we passed a solitary mushroom.

I'm thinking it might be a Psathyrella. It was only about 5 cm high and 2.5 cm across.

The gill attachment looks 'adnate' to me and I'm getting hints of a slight scaliness to the cap. I'm thinking it could be Pale Brittlestem Psathyrella candolleana. Should really do some microscopy to confirm!

It was also nice to see Chicken of the Woods Laetiporus sulphureus fruiting in the village and Dead Man's Fingers Xylaria polymorpha growing up from a rotting stump in the woods.

For the record
Date: 2 June 2018
Location: Lodsworth
Grid ref: Psathyrella sp. SU933230; L. sulphureus SU926232; X. polymorpha SU9323

Records entered into FRDBI 07/09/2018