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Allopsalliota geesterani a new invader in Britain
Field Mycology Volume 6(3), July 2005
ALLOPSALLIOTA GEESTERANI a new invader in Britain Carol Hobart 84 Stafford Road, Sheffield, South Yorkshire S2 2SF
T
he important Yorkshire bird reserve of Potteric Carr in VC 63 seemed an unlikely place to collect fungi but it has some interesting varied habitats and has produced some worthwhile records in the two years I have been visiting the site. This day, 15 August 2004 was no exception; a visit north by Mario Tortelli prompted me to arrange the visit with local mycologist Paul Ardron. The reserve stretches across railway cuttings and has been artificially created around a natural willow carr. Numerous large areas of reed beds have been constructed; these cleanse some of the dirty water that spills over from the drains of Doncaster and act as a magnet for the birds attracted to this type of habitat. Banks of soil and clinker covered with nettles, bramble and other herbaceous plants cover less woody areas, whilst bare soil banks covered in ash, birch, hawthorn and blackthorn fringe reed beds as one enters the site.This entrance area (SK 5900) has been very productive mycologically in the past. The spring of 2004 produced hundreds of Calocybe gambosum; enormous Langermania gigantea and Lepiota species also seem to favour this path edge. This particular day there was little to record, although what appeared to be a polypore edge protruding out of the bank persuaded me to investigate further. It was difficult to access. The dense prickly hawthorn and blackthorn branches barred my attempts; more agile, Paul crawled in to excavate. It was an extremely odd collection - a huge agaric approx 16 cm across, black maroon in colour and chunky, a solid mass with shallow gills that had been almost totally grazed, while what was left of them appeared honey coloured. Unfortunately the specimen was old and there was a strange fluffy brown
substance on it. Whether this was fibrous rubbish or a dirty secondary infection or ozonium it was difficult to tell. We studied this odd agaric closely but couldn’t even make out the genus. We searched around for more specimens, no luck. On our return later that afternoon, I spotted against the skyline what appeared to be an eruption at the top of the bank 50 yds from the original site. It seemed to be a cluster of the same species pushing up through the soil. This collection was in pristine condition with both young and mature specimens present. They were emerging from a confluent base; we dug around to a depth of over 20cm but it was clear we would have needed a spade to remove the group of five or six fruitbodies intact. We obviously didn’t want to destroy the whole cluster so a few representative specimens were collected. These huge, chunky basidiocarps varied in size from 10 cm across the closed caps to 15 cm when mature. The stipe of mature specimens was approx. 19 cm long to the point of attachment; and the width was 4.5 cm. The pileus seemed to be covered in a thin mycelial layer which had embedded within it particles of adhering soil. The cap, initially white, turned wine colour on handling, as did the rest of the basidiocarp. The honeycoloured gills were intact; these were shallow in section and sometimes forked near the stipe. The cap margin even in mature specimens was inrolled and there was a noticeable white area 5 mm wide overhanging the gills. The gills were seemingly free but on younger fruitbodies this junction appeared to have remnants of pinkish denticles and mycelium. The stipe on younger specimens had pinkish squames or girdles and in some fruitbodies the stipe base was distinctly marginate.When cut the fungus first turned an amazing yellow 77
Field Mycology Volume 6(3), July 2005 cult to identify it without Marijke’s description. When they emerge, the fruitbodies tend to be dark in colour and have lots of soil particles attached so they are difficult to see in the dense undergrowth. All the collections seem to have been growing very close to rabbit burrows and the stipe base may well penetrate into these. Do they obtain nutrients The author and Mario Tortelli photographing the collection of under the overhanging from enriched soil bushes. Photograph © Paul Ardron. within the warren? Do small mammals colour and then changed to deep wine-red. disperse the spores after nibbling the gills? My remark “if it had a different gill colour it There was evidence of grazing by mammals would remind me of an Agaricus” prompted and possibly slugs. The initial two groups Mario to became extremely excited. He were on a bank at the back of a black-headed reminded me of the ‘Agaricus Workshop’ we gull colony; maybe these brought the spores had both attended six weeks earlier, delivered in from Europe. No other British collection by Marijke Nauta. He felt sure it was appears to have been recorded but hopefully Allopsalliota geesterani, the former Agaricus the attached photographs will alert others to species she had moved into a separate genus this rare semi-subterranean agaric. Contact with Marijke Nauta has provided of its own; it adorns the cover of Flora Agaricina Neerlandica Vol. 5(2001) but it was further details of its distribution; she is aware of it occurring at limited sites in Germany not known in Britain. Microscopic examination proved that this and the Netherlands. She believes that origiindeed was the case; it was quite distinctive nal claims that it has been found in Israel and perfectly fitted her description in that may be mistaken as the material there has not work. Microscopically, it had the capitate exhibited the “characteristic endosporal cystidia that featured in the description. thickening or the peculiar cheilocystidia”. Macroscopically the size (15 cm), its subterranean habitat and colour changes were all Material has been lodged at the Royal exact. So here was an exciting new record for Botanic Gardens, Kew and the find has been previously reported in the Potteric Carr Britain on an otherwise unproductive day. Subsequent visits to the site have shown it annual report 2004 and The Naturalist. has been fruiting through till November and clusters of up to eleven fruitbodies have been seen. An additional collection has also been recorded at Potteric late in the season about a mile away on the edge of a rabbit burrow. How long it has been established at this reserve is unclear. It is likely that if it had been collected then it would have been diffi78
Field Mycology Volume 6(3), July 2005 Left: Allopsalliota geesterani pushing up through the soil at Potteric Carr in Yorkshire. The species grew here in clumps in the shade of dense bushes. Photograph © Carol Hobart.
Below: a close-up of the gills and cap margin showing dark droplets oozing from the tissues, a feature thought not to have been previously reported. Photograph © Paul Ardron.
Below: the fruitbodies are usually stained a dull reddish purple and bruise even darker, a very striking combination when compared with ordinary Agaricus species. Photograph © Carol Hobart.
Below: cross-section showing the yellow stains that develop in the cut flesh. Photograph © Carol Hobart.
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ALLOPSALLIOTA GEESTERANI a new invader in Britain Carol Hobart 84 Stafford Road, Sheffield, South Yorkshire S2 2SF
T
he important Yorkshire bird reserve of Potteric Carr in VC 63 seemed an unlikely place to collect fungi but it has some interesting varied habitats and has produced some worthwhile records in the two years I have been visiting the site. This day, 15 August 2004 was no exception; a visit north by Mario Tortelli prompted me to arrange the visit with local mycologist Paul Ardron. The reserve stretches across railway cuttings and has been artificially created around a natural willow carr. Numerous large areas of reed beds have been constructed; these cleanse some of the dirty water that spills over from the drains of Doncaster and act as a magnet for the birds attracted to this type of habitat. Banks of soil and clinker covered with nettles, bramble and other herbaceous plants cover less woody areas, whilst bare soil banks covered in ash, birch, hawthorn and blackthorn fringe reed beds as one enters the site.This entrance area (SK 5900) has been very productive mycologically in the past. The spring of 2004 produced hundreds of Calocybe gambosum; enormous Langermania gigantea and Lepiota species also seem to favour this path edge. This particular day there was little to record, although what appeared to be a polypore edge protruding out of the bank persuaded me to investigate further. It was difficult to access. The dense prickly hawthorn and blackthorn branches barred my attempts; more agile, Paul crawled in to excavate. It was an extremely odd collection - a huge agaric approx 16 cm across, black maroon in colour and chunky, a solid mass with shallow gills that had been almost totally grazed, while what was left of them appeared honey coloured. Unfortunately the specimen was old and there was a strange fluffy brown
substance on it. Whether this was fibrous rubbish or a dirty secondary infection or ozonium it was difficult to tell. We studied this odd agaric closely but couldn’t even make out the genus. We searched around for more specimens, no luck. On our return later that afternoon, I spotted against the skyline what appeared to be an eruption at the top of the bank 50 yds from the original site. It seemed to be a cluster of the same species pushing up through the soil. This collection was in pristine condition with both young and mature specimens present. They were emerging from a confluent base; we dug around to a depth of over 20cm but it was clear we would have needed a spade to remove the group of five or six fruitbodies intact. We obviously didn’t want to destroy the whole cluster so a few representative specimens were collected. These huge, chunky basidiocarps varied in size from 10 cm across the closed caps to 15 cm when mature. The stipe of mature specimens was approx. 19 cm long to the point of attachment; and the width was 4.5 cm. The pileus seemed to be covered in a thin mycelial layer which had embedded within it particles of adhering soil. The cap, initially white, turned wine colour on handling, as did the rest of the basidiocarp. The honeycoloured gills were intact; these were shallow in section and sometimes forked near the stipe. The cap margin even in mature specimens was inrolled and there was a noticeable white area 5 mm wide overhanging the gills. The gills were seemingly free but on younger fruitbodies this junction appeared to have remnants of pinkish denticles and mycelium. The stipe on younger specimens had pinkish squames or girdles and in some fruitbodies the stipe base was distinctly marginate.When cut the fungus first turned an amazing yellow 77
Field Mycology Volume 6(3), July 2005 cult to identify it without Marijke’s description. When they emerge, the fruitbodies tend to be dark in colour and have lots of soil particles attached so they are difficult to see in the dense undergrowth. All the collections seem to have been growing very close to rabbit burrows and the stipe base may well penetrate into these. Do they obtain nutrients The author and Mario Tortelli photographing the collection of under the overhanging from enriched soil bushes. Photograph © Paul Ardron. within the warren? Do small mammals colour and then changed to deep wine-red. disperse the spores after nibbling the gills? My remark “if it had a different gill colour it There was evidence of grazing by mammals would remind me of an Agaricus” prompted and possibly slugs. The initial two groups Mario to became extremely excited. He were on a bank at the back of a black-headed reminded me of the ‘Agaricus Workshop’ we gull colony; maybe these brought the spores had both attended six weeks earlier, delivered in from Europe. No other British collection by Marijke Nauta. He felt sure it was appears to have been recorded but hopefully Allopsalliota geesterani, the former Agaricus the attached photographs will alert others to species she had moved into a separate genus this rare semi-subterranean agaric. Contact with Marijke Nauta has provided of its own; it adorns the cover of Flora Agaricina Neerlandica Vol. 5(2001) but it was further details of its distribution; she is aware of it occurring at limited sites in Germany not known in Britain. Microscopic examination proved that this and the Netherlands. She believes that origiindeed was the case; it was quite distinctive nal claims that it has been found in Israel and perfectly fitted her description in that may be mistaken as the material there has not work. Microscopically, it had the capitate exhibited the “characteristic endosporal cystidia that featured in the description. thickening or the peculiar cheilocystidia”. Macroscopically the size (15 cm), its subterranean habitat and colour changes were all Material has been lodged at the Royal exact. So here was an exciting new record for Botanic Gardens, Kew and the find has been previously reported in the Potteric Carr Britain on an otherwise unproductive day. Subsequent visits to the site have shown it annual report 2004 and The Naturalist. has been fruiting through till November and clusters of up to eleven fruitbodies have been seen. An additional collection has also been recorded at Potteric late in the season about a mile away on the edge of a rabbit burrow. How long it has been established at this reserve is unclear. It is likely that if it had been collected then it would have been diffi78
Field Mycology Volume 6(3), July 2005 Left: Allopsalliota geesterani pushing up through the soil at Potteric Carr in Yorkshire. The species grew here in clumps in the shade of dense bushes. Photograph © Carol Hobart.
Below: a close-up of the gills and cap margin showing dark droplets oozing from the tissues, a feature thought not to have been previously reported. Photograph © Paul Ardron.
Below: the fruitbodies are usually stained a dull reddish purple and bruise even darker, a very striking combination when compared with ordinary Agaricus species. Photograph © Carol Hobart.
Below: cross-section showing the yellow stains that develop in the cut flesh. Photograph © Carol Hobart.
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