Watsonia : journal and proceedings of the Botanical Society of the British Isles

330 Pages·1992·27.8 MB·English

by  Botanical Society of the British Isles

RD&W2000

WATSONIA
Journal of the Botanical Society
of the British Isles
Volume 19 Part February 1992
1
Editors: J. R. Akeroyd, J. R. Edmondson,
R. R. Mill, E. C. Nelson, C. D. Preston,
Rushton
B. S.
ISSN: 0043-1532
Botanical Society of the British Isles
Patron: Her Majesty Queen Elizabeth the Queen Mother
AoDlicatinnsfor»«fsr«s5erslaipshouldbeaddressedtotheHon. GeneralSecretary,
itural HistoryMuseum, CromwellRoad, London,
tieSociety'sProspectusmay beobtained.
ElectedattheAnnual GeneralMeeting, 4th May 1991
President, Dr P. Macpherson
Vice-Presidents, Mr J. Ounsted, Mr P. S. Green, Dr G. Halhday,
Mr A. C. Jermy
Honorary GeneralSecretary, Mrs M. Briggs
Honorary Treasurer, Mr M. Walpole
Editors of Watsonia
PapersandShortNotes,J. R. Edmondson, R. R. Mill,E. C. Nelson,B. S. Rushton*
PlantRecords, C. D. FiQSton
Book Reviews, J. R. Edmondson
Obituaries, J. R. Akeroyd
*Receiving editor, to whom all MSS should be sent (see inside back cover).
I Bfir=
Watsonia, 19, 1-19 (1992) | ^ rr1p f^^o-
^
U2I^
Distribution of Pteridophyta in Wales
G. HUTCHINSON and B. A. THOMAS
DepartmentofBotany, NationalMuseum ofWales, Cardiff, CFl 3NP
ABSTRACT
New 10-km square maps are presented for pteridophytes in Wales. The time-spans used for these maps are
pre-1950, 1950-69 and 1970-1990.
INTRODUCTION
An interest by botany staff of the National Museum of Wales in recording the distribution of
pteridophytesinWaleshasbeenevidentsinceH.A.HydeandA.E.Wadewrotetheoriginaledition
ofWelshFerns. Thisdescriptivehandbook,publishedjointlybytheNationalMuseumofWalesand
the University of Wales in 1940, was written in response to a perceived need for a simple and
inexpensivetext. ItsusefulnessoutsidethePrincipalitywasanticipatedcorrectlybytheinclusionof
briefaccountsofBritishspeciesnotoccurringinWales. Notesweregivenonthedistributionofthe
species in Wales and lists included ofspecimens in the Welsh National Herbarium. Specimen lists
forthe verycommon specieswere impractical so onlyvice-countieswere listed.
This system was followed in the next three editions, published in 1948, 1954 and 1962, although
the third edition was largely a lithographical reprint ofthe second. There were, however, several
changesinthefourth editionwhich reflectedanincreased knowledgeofferndistributioninWales.
The three species of Polypodium, the two subspecies ofAsplenium trichomanes, and hybrids of
Asplenium and Polystichum were included for the first time. Details of Dryopteris hybrids were
expanded. ThevarietiesofAsplenium,Athyrium, Ceterach, Cystopteris and Dryopteris, whichhad
been included earlier, were omitted.
The larger fifth edition (1969) was revised and expanded by S. G. Harrison, to include the
clubmosses, quillworts and horsetails. The sixth edition (1978) gave many more descriptions of
hybrids with corresponding details oftheir known distributions in Wales.
Throughout these six editions there was a marked increase in the number of Hsted herbarium
specimens, thereby giving greater information on species, subspecies and hybrid distributions in
Wales. Forexample,thenumberoflistedspecimensforPhegopterisconnectilisincreasedfrom20to
51 and for Hymenophyllum wilsoniifrom 22 to 66. There is aclearincrease in the number ofsites
Hstedformany taxaandtherefore agreaterknowndistributionforthem. More specieslistssimply
became too large so they were omitted when every vice-county in Wales was represented. The
authorsalso recorded the overall increase in the total numberofspecimens heldinthe herbarium.
NumbersofBritishfernsweregivenas 1,660in 1940, 1,990in 1948,2,200in 1954and2,260in 1962,
then the number ofBritish Pteridophyta as 3,200 in 1969 and 3,900 in 1978. The herbarium now
includes 6700 British Pteridophyta ofwhich 3900 are Welsh.
Meanwhile, there was the general move towards recordingthe distribution ofplants by the grid
square system, rather than by vice-counties, and the publication of the Atlas ofthe Britishflora
(Perring&Walters1962).Thepteridophytemapsinthelatterwere,however,widelyacceptedtobe
imperfect because they went to the printers within six years of the start of the mapping scheme
(Jermy etal. 1978). Thiswas rectified considerablywhen theAtlas ofFerns ofthe British Isleswas
pubhshed (Jermy et al. 1978). Even so, some of these later maps were clearly still incomplete,
especially those of the commonly less well understood species, hybrids of Polypodium and
Dryopteris, and the subspecies ofAsplenium trichomanes and Dryopteris affinis.
Itwasagainstthisbackgroundofrecordingthedistributionsofpteridophytesthatwecommenced
work on a new edition of Welsh Ferns. Clearly, the idea of incorporating lists of herbarium
Botanical Society of the British Isles
Patron: Her Majesty Queen Elizabeth the Queen Mother
Applicationsformembershipshould beaddressedtotheHon. GeneralSecretary,
c/oDepartmentofBotany, TheNaturalHistoryMuseum, CromwellRoad, London,
SW75BD, fromwhomcopiesoftheSociety'sProspectusmaybeobtained.
Officers for 1991-92
ElectedattheAnnual GeneralMeeting, 4th May 1991
President, Dr P. Macpherson
Vice-Presidents, Mr J. Ounsted, Mr P. S. Green, Dr G. Halliday,
Mr A. C. Jermy
Honorary GeneralSecretary, Mrs M. Briggs
Honorary Treasurer, Mr M. Walpole
Editors of Watsonia
PapersandShortNotes,J. R. Edmondson, R. R. Mill, E. C. Nelson,B. S. Rushton*
CD.
PlantRecords Preston
,
Book Reviews, J. R. Edmondson
Obituaries, J. R. Akeroyd
*Receiving editor, to whom all MSS should be sent (see inside back cover).
Watsonia, 19, 1-19 (1992) A,r*srp
Distribution of Pteridophyta in Wales
G. HUTCHINSON and B. A. THOMAS
DepartmentofBotany, National Museum ofWales, Cardiff, CFl 3NP
ABSTRACT
New 10-km square maps are presented for pteridophytes in Wales. The time-spans used for these maps are
pre-1950, 1950-69 and 1970-1990.
INTRODUCTION
An interest by botany staff of the National Museum of Wales in recording the distribution of
pteridophytesinWaleshasbeenevidentsinceH.A.HydeandA.E.Wadewrotetheoriginaledition
ofWelshFerns. Thisdescriptivehandbook,publishedjointlybytheNationalMuseumofWalesand
the University of Wales in 1940, was written in response to a perceived need for a simple and
inexpensivetext. ItsusefulnessoutsidethePrincipalitywasanticipatedcorrectlybytheinclusionof
briefaccountsofBritishspeciesnotoccurringinWales. Notesweregivenonthedistributionofthe
species in Wales and listsincluded ofspecimens in the Welsh National Herbarium. Specimen lists
forthe verycommon specieswere impractical so onlyvice-countieswere listed.
This system was followed in the next three editions, published in 1948, 1954and 1962, although
the third edition was largely a lithographical reprint ofthe second. There were, however, several
changesinthefourth editionwhich reflectedan increasedknowledgeofferndistributioninWales.
The three species of Polypodium, the two subspecies ofAsplenium trichomanes, and hybrids of
Asplenium and Polystichum were included for the first time. Details of Dryopteris hybrids were
expanded. ThevarietiesofAsplenium,Athyrium, Ceterach, Cystopteris andDryopteris, whichhad
been included earlier, were omitted.
The larger fifth edition (1969) was revised and expanded by S. G. Harrison, to include the
clubmosses, quillworts and horsetails. The sixth edition (1978) gave many more descriptions of
hybrids with corresponding details oftheir known distributions in Wales.
Throughout these six editions there was a marked increase in the number of Hsted herbarium
specimens, thereby giving greater information on species, subspecies and hybrid distributions in
Wales. Forexample,thenumberoflistedspecimensforPhegopterisconnectilisincreasedfrom20to
51 and forHymenophyllum wilsoniifrom 22 to 66. There is aclearincrease in the numberofsites
listedformanytaxa andtherefore agreaterknowndistributionforthem. Morespecieslistssimply
became too large so they were omitted when every vice-county in Wales was represented. The
authors also recordedtheoverall increaseinthe totalnumberofspecimens heldinthe herbarium.
NumbersofBritishfernsweregivenas 1,660in 1940, 1,990in 1948,2,200in 1954and2,260in 1962,
then the number of British Pteridophyta as 3,200 in 1969 and 3,900 in 1978. The herbarium now
includes 6700 British Pteridophyta ofwhich 3900 are Welsh.
Meanwhile, there was the general move towards recording the distribution ofplants bythe grid
square system, rather than by vice-counties, and the publication of the Atlas ofthe Britishflora
(Perring&Walters1962).Thepteridophytemapsinthelatterwere,however,widelyacceptedtobe
imperfect because they went to the printers within six years of the start of the mapping scheme
(Jermy etal. 1978). This was rectified considerably when theAtlas ofFernsofthe British Isleswas
pubhshed (Jermy et al. 1978). Even so, some of these later maps were clearly still incomplete,
especially those of the commonly less well understood species, hybrids of Polypodium and
Dryopteris, and the subspecies ofAsplenium trichomanes and Dryopteris afftnis.
Itwasagainstthisbackgroundofrecordingthedistributionsofpteridophytesthatwecommenced
work on a new edition of Welsh Ferns. Clearly, the idea of incorporating lists of herbarium
M!575 HUTCHINSON AND B. A. THOMAS
norisitasuitablemethodofportrayingthedistributionoftaxa. We
0-.,^., bution on a 10-km grid square system. With the completion ofthe
O 987-88) and talk ofa new atlas ofthe British flora, although funds
I
, ^ . )0isaconvenientdatetoendthecurrenttimespan. These mapswe
presenthere,inadvanceotanewWelshFerns,toensuretheirearlyavailabilitytoawideaudiencein
the hope that these will stimulate further interest in Welsh pteridophytes and their distribution.
COMPILATION OF MAPS
The base-maps used were those of Perring & Walters (1962) and Perring & Sell (1968) with
nomenclature modifiedaccordingtoDerricketal. (1987). Tothesewere addedrecordsheldbythe
Biological Records Centre, Monks WoodExperimental StationinNovember 1986whichincluded
NMW
all the records ofJermy etal. (1978). Information from all the specimens at was checked as
was that from specimens ofthe more critical taxa at BM. Appropriate literature sourceswere also
NMW
checked. The records in the Welsh Plant Records data-files held at were added (including
records received which applied up to the end of 1990).
Updatedmapswere sent, formodification andcomment, to allWelshvice-countyrecorders and
several interested members ofboth the B.S.B.I. and the British Pteridological Society. However,
maps ofthose taxaconsideredtobe rarewere onlysenton avice-countybasistotherelevantvice-
county recorder(s). Several records were added at this stage and recorders were also able to point
out former mapping errors. A healthy correspondence on queries followed, which included
obtainingmoredetailsfromrecordsattheBiologicalRecordsCentre. Generally,thewishesofvice-
county recorders were complied with, especially the removal of doubtful records. Untraceable
recordswerenotusedforthemapsandontheboundarywithEnglandonlyrecordsfromtheWelsh
side ofthe 10-km square were included. The 10-km square recordswhich appeared in theAtlas of
theBritishflora as 1930 onwardsthatcould notbe traced are given aseparatesymbolbecausethey
cannot be assigned to either side ofthe 1950 time span boundary used in our maps.
Followingthisstageoftheworkithasbeenpossibletoaddnumerousrecordsthatresultedmostly
either from field work associated with current county flora surveys or determinations of new
specimens sent to NMW. Finally, the pteridophyte maps compiled from the B.S.B.I. Monitoring
Scheme (1987-1988) were added.
The maps arepresentedinFigs 1-84, arrangedin alphabetical order. Symbolsusedforthe maps
are as follows:-
•
1970-1990
€
1950-1969
0
1930-1969 untracedAtlas ofthe Britishflora record
O
pre-1950
^
Introduced 1970-1990
Introduced pre-1970
<C>
Criticaltaxahavebeenlookedatverycarefullyandmanyspecimensofthemexamined. Mapsfor
the main ones, which are outhned here, are still considered incomplete.
Asplenium trichomanes L. Since the Atlas ofthe Britishflora, a new subspecies {A. trichomanes
subsp.pachyrachis (Christ) Lovis & Reichst.) and a nothosubspecies {A. trichomanes nothosubsp.
staufferi Lovis & Reichst.) have been identified for Wales (Rickard 1989). A. trichomanes subsp.
trichomanesisconsideredunder-recordedespeciallyinthesouthernhalfofWales. Newrecordsfor
this area were only accepted after microscopic measurement of the exospores according to the
methodofReichstein (Hegi 1984).TheA. trichomanesdistributionmapisidenticalwiththatiorA.
trichomanes subsp. quadrivalens D. E. Meyer emend. Lovis, and is omitted.
Dryopteris affinis (Lowe) Fraser-Jenkins. An understanding of Dryopteris affinis as comprising
threesubspeciesintheBritishIsleshasonlyemergedinthesecondhalfofthe 1980s(Fraser-Jenkins
1987). Var. paleaceo-lobata sensu Fraser-Jenkins is included under subsp. affinis and var. robusta
(Oberholzer & von Tavel ex Fraser-Jenkins) Fraser-Jenkins & Salvo under subsp. borreri
(Newman) Fraser-Jenkins, but records ofthese varieties were almost zero.
Polypodium vulgareL. agg. The recordsofPolypodium vulgarewere treatedwithcaution as many
appliedtoP. vulgaresensulato. Whereaccurateidentificationcouldnotbeestablishedrecordswere