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THE FUNGI OF YNYSLAS SAND-DUNESA Preliminary Survey

By M ROTHEROE, J HEDGER AND J SAVIDGE

Department of Botany & Microbiology, UCW Aberystwyth

Coastal sand-dunes provide remarkablyrich and varied habitats for fungi, yet,with some notable exceptions, theirstudy has been neglected by fieldmycologists.

The year 1985 was abnormally coldand wet and most forayers at inland siteswill remember it as being a particularlypoor season for macromycete fruiting.This contrasted dramatically with the ex­perience of the authors who were engag­ed in a preliminary survey of the largerfungi of Ynyslas nature reserve, a sand­dune system on the Dyfi estuary nearBorth in Mid-Wales. Approximately fort­nightly visits throughout the year (by MR) revealed an unexpectedly prolificfungus flora, embarrassingly so at peakperiods when large numbers of un­familiar species competed for identifica­tion. On one visit in October, 50 different

agaric species were collected - whichwas one more than the total number ofagarics previously recorded from thesite.

The habitats at Ynyslas vary from thebare sand of mobile dunes next to thesea, through fixed and rabbit-grazed turfto the periodically flooded slacks.

Typical of the mycoflora of the mobiledunes are PsathyreIIa ammophiIa (Dur.& Lev.]Orton, which fruited almost con­tinuously from April to November, oftenin troops, a number of Melanoleucaspecies, PhaIIus hadriani Vent.: Pers. andP impudicus L: Pers. and Peziza am­mophiIa Dur. & Mont., a cup fungus witha rooting pseudostipe. Ynyslas was, un­til 1985, the only known British locationfor a coprophilous bird's nest fungus,Cyathus stercoreus (Schwein.) de Toni,which is usually found anchored to the

Miss Sally Pester, a summer warden at Ynyslas Nature Reserve makes a wish ina Fairy Ring of Sand-dune Earth Stars (Geastrum nanum), August 1985.

bases of marram grass stems by aggrega­tions of sand. It has now been found atthree other Welsh dune systems.

Several agaric and gasteromycetespecies fruit in rings up to 20m indiameter on the fixed dunes and inslacks. The rate of growth of the ringscan be as much as O.5-lm in diameter peryear. Abundant in these habitats wereOmphalina pyxidata (Bull.: Fr.] Quel., inregular flushes throughout the winterand autumn months in 1985, and thefairy ring champignon, Marasmiusoreades (Bolton: Fr.) Fr., from May toNovember.

Equally common in these areas werethe pint-sized parasol mushroom,Macrolepicta konradii (Huijsm ex Orton)Moser, and, remarkably, a variety oftheyellow-staining mushroom, Agaricusxanthoderrnus Gen. var lepiotoides RMaire, which is not in the British CheckList. The latter was frequently collectedby visitors to the reserve for culinarypurposes - until the strongly chromeyellow bruising was pointed out. Among

....r _ _ •

Geastrum nanum, Ynyslas NatureReserve, August 1985.

11 species of Hygrocybe recorded, Heonieoides (Orton) Orton & Watl. and Heoniea (Scop: Fr.) Kummer, often form­ed dense miniature forests in the slacksfrom July to November, while H auran­tioluteseens Orton, H langei Kuehner andH oehraeeopaIIida Orton, were recordedon a third of all visits.

The Bolbitiaceae are well-representedat Ynyslas, comprising about 12% of thetotal agaric flora. A fungus agreeing withAgroeybe arenaria (Peck) Singer, wasfound on four occasions in the semi­fixed dunes and several collections weremade of a large-spored form of A semior­bieularis (Bull.) Fayod, which iswidespread although it does not appearin the literature as such. This hassometimes been referred to as A semior­bicularis var macrospora.

Another species not in the Check List,Inocybe vulpinella Bruyl, was the secondmost frequent agaric recorded, beingfound on every visit from May toNovember, always adjacent to bushes ofSalix atrocinerea. Uncommon species ap­pearing towards the end of the year in­cluded Lepista irina [Fr.] Bigelow,Melanoleuca cinereifolia (Bon) Bon andTubaria paIIidospora J Lange.

Gasteromycetes abound on the fixeddunes, the protean Vascellum protense(pers.) Kreisel, being the most prolificand Tulostoma brumale Pers.: Pers., for­ming numerous colonies. The dunespecies Geastrum nanum Pers. was abun­dant and at one spot formed a fairy ring,1.5 metres across, with successive fruitbodies appearing over a two-monthperiod. A second earth star, G badiumPers., known previously from only westCornwall and west Norfolk, was alsorecorded at Ynyslas for the first time dur­ing the survey.

Among the ascomycetes, several earthtongues fruit gregariously in dune slacksand slopes, including Trichoglossumrasum Pat., the only other British recordof which is believed to be from Braun­ton Burrows.

The final recording visit, made on 27December in icy conditions after twodays of sub-zero temperatures, deservesspecial mention. The best collections of

17the survey of Agaricus devoniensis Ortonwere made on this occasion, whilstamongst the other 26 freshly fruiting butmostly frozen agarics noted wereClitocybe barbularum (Romagn.) Orton,Cystoderma jasonis (Cooke & Massee)Harmaja, Laccaria striatula (Peck) Peck,Melanoleuca cinerasens Reid and Mschumacheri (Fr.) Singer, Mycenellasalicina (Vel.) Singer and Omphalinaobscurata Reid.

H was clear from this survey thatYnyslas, as well as other older dunesystems where comparative collectionswere made, provides excellent oppor­tunities for the investigation of lessfamiliar species in a number of fungalgroups. Those interested in sampling thedelights of sand dune habitats will notethat a BMS weekend workshop based atAberystwyth has been arranged for thispurpose in September this year (1987).

A complete list of species is availablefrom the authors who are indebted to theNature Conservancy Council for a granttowards travelling expenses and toDavid Pegler, Brian Spooner and RoyWatling for identification of criticalspecies.

The survey continues and we hope toproduce a more comprehensive accountof the taxonomy and ecology of sanddune fungi in a few years' time.