Notes & Records

Vol 13 (4)

NOTES & RECORDS Alick Henrici*

his is being written at the end of August in a notably wet summer. So why has it proved such a poor year over most of southern England for the Russulas and Boletes that should flourish in early autumn? Too wet? Usually the trouble is ‘too dry‘. Having no answers to such questions I pass quickly on to other topics.

marketed as an ingredient of some 30 health products. Though now in a different genus from O. sinensis it is equally a source of cordycepin. Commercial cultivation was initially on insects, chiefly silkworms (larvae of Bombyx mori) but recently it has been found possible to use nothing more exotic than a mixture of brown rice, malt and soya beans. This was unexpected and remains unexplained in a naturally obligate parasite. It is also less than half the cost of using silkworms, both in turn very much cheaper than paying market prices for O. sinensis. However debate rages on the supposed inferior quality of anything not grown from insects. There is much ongoing research in pursuit of optimum strains and into ways of avoiding their unfortunate tendency to degenerate after only one or two subcultures. C. militaris occurs worldwide and is also widespread in Britain. It is reported on 12 families of moths and also a few other insects. When found the host can usually be located with careful excavation, but the combination of host condition and collector expertise is seldom sufficient to allow identification to species level. Almost all the extensive British material in Kew has no host details at all, or at most ‘insect pupa‘ or ‘moth larva‘. Only three collections are more specific: larva of Yellow Underwing, larva of Fox Moth, pupa of ?Cabbage Moth.

T

Research into Cordyceps militaris Readers will be aware of the remarkable ‘Caterpillar Fungus’ Cordyceps sinensis (recently moved to the segregate genus Ophiocordyceps), famous for the near miraculous range of healthgiving properties ascribed to it. It received worldwide publicity as a reputed contributor to Chinese success at the 2008 Beijing Olympics. It grows only in the high altitude grasslands of the Tibetan Plateau and neighbouring areas of Nepal, Bhutan and India, where it has been severely over-collected and now commands very high prices. It has temporarily transformed the economies of these areas — see Winkler (2010) in FM11(2) for a vivid account of this trade. I only recently became aware of the immense boost thus given to research on the familiar British species C. militaris. The following notes are largely derived from Shrestha et al. (2012), an overview of recent research into C. militaris and its commercial development. These authors cite over 200 further references, most published in the last ten years by Chinese authors, including a report in 2011 of the sequencing of the entire C. militaris genome. Briefly the facts are these. Most of the beneficial effects claimed for cordycepin, the main active ingredient in the stroma of C. sinensis, are real enough — contrast similar claims for rhino horns! But C. sinensis has so far resisted all attempts at artificial cultivation, despite success with numerous related species. Much research has thus been concentrated on C. militaris, relatively easily cultured and with a similar but lesser reputation. This is widely used in China as an additive to soups and stews, and currently

Other British species of Cordyceps s.l. In this context, an update on the other Cordyceps species known in Britain may be useful. I am grateful to Brian Spooner and to Don McNeil for comments and corrections to a first draft of the notes that follow. Most species are described and illustrated in Dennis (1981) but there have since been numerous name changes. They have been little studied in Britain since the extensive work of Petch on entomogenous fungi worldwide, leading to a British checklist (Petch, 1948). There are surely further discoveries to be made. There are thought to be at least 400 known species but few of them European and only 11 currently on

*8 Victoria Cottages, Sandycombe Rd., Richmond, Surrey TW9 3NW

doi:10.1016/j.fldmyc.2012.10.011

141

Vol 13 (4) the British list. What’s more, four of these are each known from only a single British site, reinforcing the words of M.C. Cooke (1892) who wrote “Unfortunately many of the species of Cordyceps are almost the rarest among fungi, so anything like a critical estimate of species cannot be undertaken in such a dearth of specimens”. A recent major multi-gene DNA study covering 162 species (Sung et al., 2007) has shown that traditional Cordyceps splits into three genera, very clearly separated in DNA terms, much less so in morphology. The 11 British species fall into Cordyceps (2), Elaphocordyceps (3) and Ophiocordyceps (6). In Cordyceps itself we have only the type species C. militaris (Fig. 1) and one other, listed by Dennis following Petch as C. tuberculata. True C. tuberculata is now known to be largely tropical though possibly also present in southern Europe. The British material so named is, at least in part, C. bifusispora, distinguished by its typical immensely long Cordyceps spores being swollen at their two ends. This is a small species parasitising moth pupae or sometimes the moths themselves. C. tuberculata sensu Dennis is considered by Dissing (2000) a straight synonym of C. bifusispora, but there may be more than one species involved. Elaphocordyceps, as might be expected, contains the three British species parasitic on Elaphomyces (though in a world context also a few species on insects). E. ophioglossoides is fairly common, E. capitata and E. longisegmentis less so - their relative frequency is unknown as they are very similar in the field. E. longisegmentis was widely known in the past as C. canadensis, but that name is properly a synonym of E. capitata. Ophiocordyceps is now much the largest of the three genera, but only two species are at all well known in Britain:* O. gracilis: fairly often collected, usually in spring, often (always?) on larvae of the moth genus Hepialus, which has five British species. The main host appears to be the Common Swift (H. lupulinus) as in the recent collection discussed by Hodge (2012) in FM13(1). It isn’t closely related to O. sinensis even though the ghost moths infected by O. sinensis in Tibet also belong to the Hepialidae. * O. forquignonii: small and very inconspicuous on flies, considered by Dennis probably not uncommon in woodland, especially in the north.

O. myrmecophila on ants is very similar but two old Welsh records under this name at Kew are unconvincing and it has never been accepted as British. Two more species have been found once each by E.A. Ellis at Wheatfen Broad in Norfolk and confirmed by Petch: O. memorabilis on a beetle larva in 1947 and a collection named as O. sphecocephala, a species parasitic on bees and wasps but found detached from its host in 1942. However, this is now thought to be an exclusively tropical species. European collections so named probably all belong to O. ditmarii. The final two species might be considered extinct in Britain except that nobody really knows:— * O. entomorrhiza: relatively conspicuous on beetle larvae with a dark stipe and pale club. It was convincingly reported by Dickson (1785!) from Bulstrode in Bucks but has not been seen since. The epithet ‘entomorrhiza’ was subsequently widely misapplied to O. gracilis. * O. clavulata: minute but very distinctive, found by the incomparable collector C.E. Broome on scale insects (Lecanium sp. which he and Berkeley misinterpreted as sclerotia) on wychelm in Batheaston, Somerset in March 1860 and again in October that year. It has never been found again in Britain despite the encouragement of a spectacular illustration in Dennis (1981). This picture was however very recently acknowledged as responsible for its recognition new to France in December 2011, enthusiastically written up and illustrated by Moingeon & Moyne (2012), who found it on a similar looking scale insect. They could trace very few European records, but it is somewhat commoner in N. America where it was first described. The key by Dissing (2000) in Nordic Macromycetes Vol.1, covers nearly all the British species, treated in the single genus Cordyceps. For superb photos of many of these and a wide range of others see Imazeki & Hongo (1988). Most of the species above have known anamorphs assigned to a wide range of genera. These are often commoner than their teleomorphs but difficult to identify when found alone and outside the scope of this account, except to note that Don McNeil (pers. comm.) has found that the brownish white spikes of the Hymenostilbe muscaria anamorph of O. forquignonii are “at least five times commoner” than the perfect state, and

142

Vol 13 (4) often found in some numbers when found at all. For currently accepted anamorph names see Sung et al. (2007). On the 2012 BMS Upland Foray on the Isle of Bute only the two commonest species, C. militaris and E. ophioglossoides were recorded. For a fine photo of the latter, taken in Bute by Rick Wright, see the back cover of this issue. It was growing under beech by a roadside and its carefully exposed host was Elaphomyces granulatus.

‘some’ appeared as ‘none’ having been initially mistyped as ‘sone‘ and then miscorrected. In the companion article in the previous issue I wrongly stated that there were no gilled members of the order Polyporales, overlooking Faerberia, Lentinus and Panus. Also Fig.1 on p.70 omitted an intended asterisk against Trechisporales marking it as one of five orders containing only corticioid taxa. * A year ago (FM12(4):136) I discussed Anthony Carter’s first British records of Hypholoma tuberosum (from a mulched bed in a Liverpool allotment in 2009 and 2010). He reports that it has reappeared there in 2011 and 2012. I failed to note that there was already a good description of European material in Noordeloos (1999) as Psilocybe tuberosa, based on material from Belgium. A further account and illustrations are now available in Noordeloos (2011) citing references suggestive of a worldwide spread from an unknown point of origin. First described from Canada in 1987, reports from at least the following countries have since been published: 1992 Australia, 1998 Belgium, 2000 Japan, 2002 Germany, 2007 USA, 2008 China and New Zealand, 2009 Czech Republic, 2011 Britain, 2012 Denmark. This is comparable to the spread of two other wood-chip-loving species: Agrocybe rivulosa (origin equally unknown) and Leratiomyces ceres (= Stropharia aurantiaca s.auct., probably from Australia), both now abundant in Britain. H. tuberosum has so far only spread “some ten feet away” from its original site and has not yet been reported elsewhere in Britain. * In the same article I discussed Porpoloma spinulosum and suggested it was unlikely to be closely related to the generic type species, the S. American mycorrhizal P. sejunctum. Since then Martin Bidartondo (pers. comm.) has kindly sequenced the ITS regions of collections assigned to each of the three British Porpoloma species, the other two being P. e1ytrodes and P. metapodium. The results showed that no two of these were at all closely related, nor did any of tbem have an obvious home in any other genus represented in GenBank as of October 2011. No sequence was available to allow comparison with P. sejunctum.

Genome sequencing I mentioned above that the complete genome of Cordyceps militaris had been sequenced. A few years ago sequencing the human genome involved big budgets and a big team, in fact rival teams, and its completion in 2003 was big news. Things have already moved on a long way. Just how far is shown by a recent note (Spatafora, 2011) announcing “1000 fungal genomes to be sequenced”. The author is part of an international research team working in collaboration with the Joint Genome Institute of the US Department of Energy that has embarked on a five-year project to sequence at least two reference genomes from every accepted fungal family. The plan is to sequence 100 species from 55 families in year one and c.225 species each year for the next four years. Funding appears to have been obtained by tying this objective to research into how fungi break down polymers. This in turn is to lead to improved use of fungi in the development of alternative fuels, carbon sequestration and bioremediation. Whatever else is achieved the results are sure to provoke debate on which ‘accepted‘ fungal families are worthy of this status. Soon after reading this note I heard on the radio of evidence just published in Nature that in humans the older the parents the more the DNA of their offspring differs from what might he expected. I note this here not so much for the finding itself as the fact that it has been possible to sequence the complete genomes of enough people to produce significant results all within the budget of a single academic research project. Some additions and corrections * In the last issue I intended to write (p.107 Line 1) that some of the NCL 1960 families of Agarics had since been split or merged. Unfortunately

143

Vol 13 (4)

References

Noordeloos, M.E. (2011). Strophariaceae s.1., Fungi Europaei 13. Candusso. Petch, T. (1948). A revised list of British entomogenous fungi. Trans. Br. Mycol. Soc. 31: 286-304. Shrestha, B., Zhang, H., Zhang, Y. & Liu, X. (2012). The medicinal fungus Cordyceps militaris: research and development. Mycol. Progress 11: 589-614. Spatafora, J. (2011). Fungi: 1000 genomes. IMA Fungus 2(2): 41. Sung, G-H, Hywel-Jones, N.L., Sung, J-M., Luangsa-ard, J.J., Shrestha, B. & Spatafora, J.W. (2007). Phylogenetic classification of Cordyceps and the clavicipitaceous fungi. Stud. Myc. 57, CBS, Utrecht. Winkler, D. (2010). Cordyceps sinensis - a precious parasitic fungus infecting Tibet. Field Mycol. 11(2): 60-67.

Cooke, M.C. (1892). Vegetable Wasps and Plant Worms. SPCK, London. Dennis, R.W.G. (1981). British Ascomycetes. J. Cramer. Dickson, J. (1785). Fasciculus Plantarum cryptogamicarum Britanniae. Dissing, H. (2000). Clavicipitaceae (in Nordic Macromycetes Vol.1). Nordsvamp. Hodge, V. (2012). Two uncommon spring fungi from West Sussex. Field Mycol. 13(1): 34-36. Imazeki, R. & Hongo, T. (1988). Fungi of Japan. Yama-Kei, Tokyo. Moingeon, J-H. & Moyne, G. (2012). Ophiocordyceps clavulata (Schwein.) Petch. Une espece quasi disparue d’Europe, retrouvée sur le site du marais de Saone. Bul. Mycol. Bot. Dauphiné-Savoie 206: 13-20. Noordeloos, M.E. (1999). ‘Psilocybe’ in Flora Agaricina Neerlandica Vol.4. A.A.Balkema, Rotterdam.

BOOK REVIEWS yes, it would have been nice to see the sectioned flesh for

COLLINS FUNGI GUIDE

diagnostic colours and, yes, Tylopilus could have

Stefan Buczacki

swapped places with Leccinum variicolor. The labels for

ISBN 978 0 00724290 0 (hardback). £35 list price.

X. chrysenteron and X. chrysonemus are muddled and it

he high quality of this new Collins series of guides

T

may well be true that it’s not the most convincing red-

continues, and the laudable intention of making

cracked bolete you’ll ever see. But (and this is where

each one the most comprehensive in its field, has been

the glass half full thing comes in) let’s not forget that we

realised. It does what it says on the tin (or in this case

have illustrated, for the very first time in a guide such

dust jacket): it is the most complete field guide ever

as this, Xerocomus silwoodensis, X. chrysonemus, X.

produced. With 2300 species it out-guns the previous

bubalinus, X. engelii, X. cisalpinus, X. ripariellus,

Collins guide by Courtecuisse & Duhem by some 550

Paxillus

species, and Marcel Bon’s earlier offering by a massive 800 species.

P.

validus,

Leccinum

cyaneobasileucum in its two

colour forms. In the text we are told that the flesh of

But there is “trouble at t’mill” as well…. or “at t’net”

X. pruinatus turns apricot overnight. Outside specialist

at least. One does not need to look far on the Internet to

works like Field Mycology or Funga Nordica where is

find some scathing reviews dismissing this book out of

the general public meant to get this stuff?

hand. Problems with text, problems with illustrations,

Though some of the art does seem to poorly capture

no keys, badly organized, things in the wrong place,

the jizz of a species, there are some jewels to be found if

mislabelled species, unreadable index, etc, etc…

you

There are some highly critical people out there,

look,

e.g.

Rhodotus

palmatus,

Coprinopsis

ephemeroides, Flagelloscypha pilatii, Chromocyphella

already talking about this book being remaindered. But

muscicola, Gymnopilus dilepis, Amanita inopinata,

let us just take a deep breath for a moment and in glass

Crepidotus

half empty/half full terms let’s look a little closer at

autochthonus,

Lycoperdon

radicatum.

Lepiota, Marasmius, Coprinus (in the broad sense) and

what is actually in the glass. Walk into any bookstore

Flammulaster are particularly good. There are some

and look at the mycology section, and compare it to the

great images here to delight us.

bird, gardening, pet or plant shelves. The point is we are

Take the time to actually read the text and there are

not blessed with such a vast array of mycological books

well-researched important tips here too: where to look

of this sort that we can afford to just dismiss this new

for Cyphellostereum laeve, or remember to look for

and important offering. Yes, it would have been nice to

clamps in ‘Pluteus cervinus’ on conifers. Hunt for

have more examples of young and old fruit bodies and

doi:10.1016/j.fldmyc.2012.10.012

obscurosporus,

schistophilum, and L.

Conocybe dumetorum on decaying dog’s mercury stems

144