A synopsis of the annual species of Cyperaceae from central and southern Western Australia

41 Pages·1997·10.5 MB·

by  B L Rye

Nuytsia 11(3):383-423(1997) 383
A
synopsis ofthe annual species ofCyperaceaefrom central
W
andsouthern esternAustralia
B.L.Rye
Western Australian Herbarium, Department of Conservation and Land Management,
Locked Bag 104, Bentley Delivery Centre, WA 6983
Abstract
Rye, B.L. A synopsis ofthe annual species ofCyperaceae from central and southern Western
Australia. Nuytsia 11 (3):383-423(1997). Asynopsis,keysanddistributionmapsareprovidedforall
theannualspeciesofCyperaceaeknown fromtheEremaeanandSouth WestBotanicalProvincesof
Western Australia. Selected species are illustrated. Some taxa are ofconservation significance,
includingaboutsixspecieseachknownfromonlyonecollection.
Introduction
TherecentaccountofthefamilyCyperaceaein“FloraoftheKimberleyRegion”(Rye 1992)gives
keys,descriptionsandillustrationsforspeciesoccurringintheNorthernBotanicalProvinceofWestern
Australia. ForregionssouthoftheKimberley,thereisnorecentcomprehensivetreatmentofthefamily,
althoughtherearekeysavailableformostofthespeciesbelongingtoFimbristylis(Latz1990)andgenera
relatedtoScirpusL.(Wilson 1981).Thekeytosouth-westernCyperaceaepublishedbyBlackall&Grieve
(1954)hasneverbeenrevised.
InordertodeterminewhichspeciesofCyperaceaefromthelesswelldocumentedareasofWestern
AustraliashouldbeplacedontheDeclaredRareandPriorityFloraList,herbariumspecimensfromthe
EremaeanandSouthWestBotanicalProvincesweresurveyed. Amongthenumerousperennialsinthe
family,theproportionofspecies1ikelytobeatriskofextinctionseemedverysmal1incomparisonwith
manyotherplantfamilies. AnnualspeciesofCyperaceaeappearedtobemoreinneedofattention. Nine
newannualtaxa,nearlyallinthegenusSchoenus,weredistinguishedasaresultbothofthissurveyand
recentcurationbyKarenWilson(NSW). Threeofthesewerenamedanddescribed(Rye1997);theothers
wereallocated phrasenamesbutconsideredtobetoopoorlyknowntonameformally. Sincethen,a
further new annual taxon has been discovered and given the phrase name Schoenus sp. Waroona
(G.J.Keighery12235).
Thispaperprovides asynopsis, keysanddistribution mapsforthe annualspeciesofCyperaceae
occurringintheEremaeanandSouthWestBotanicalProvincesofWesternAustralia. Asafurtheraid
to identification ofthese plants, previously published illustrations are cited and new illustrations
providedwhererequired.
384 Nuytsia Vol. II, No. 3 (1997)
Abouthalfofthe 156speciesincludedintheKimberleyfloraareannuals,includingseveralgenera
thatdonotoccurelsewhere in WesternAustralia. In the south-westmostspecies are perennial; for
example,intheareacoveredby“FloraofthePerthRegion” lessthanaquarterofthespeciesareannuals
(Rye1987). Manyoftheannualspeciesaresmallandinconspicuous,aswellasbeingabsentaltogether
forpartofeachyear,sotendtobepoorlycollected. SincethePerthregionalflorawascompleted,eight
additional annual specieshavebeen recorded in thatregion.
Inmanyoftheperennialspecies,maximumfruitsethasbeenreducedtooneortwonutsperspikelet,
andvegetativespreadbyrhizomesisofgreatimportance. Annualspeciesneedtoproduceagoodseed
cropeachyeartoensurefuturegenerationsandalmostinvariablyproducelargernumbersofnutsper
spikeletorcondensedspike. Sincefruitingquicklyfollowsfloweringinannuals,floweringandfruiting
generally occur in the same months. The flowering and fruiting periods given here apply only to
specimens collected in the study area, as do anymeasurements andotherdescriptions.
Distributionpatternsandnewrecords
Mostspecies ofCyperaceaehavewide distributions, often extendingto otherstatesofAustralia
andoverseas. Theannualspeciesoccurmainlyinseasonallydamphabitats, includingthemarginsof
watercouses,low-lyingflatsandrockcrevices. Ofthe48namednativespecies includedhere, 13 are
endemictothesouth-westandonetothePilbaraareaofWesternAustralia. Fivespecies(Fimbristylis
ammobia,Fuirenaincrassata, F. nudiflora,IsolepisaustraliemisandSchoenuscentralis)areknown
fromlessthanfivelocalitiesinthisStatebuthavebeencollectedmorefrequentlyfromotherpartsof
Australia,whiletheremainingspecieshavebeenwidelycollectedbothinWesternAustraliaandoutside
theState. TheWesternAustraliandistributionsofallthespeciesareshowninFigures 1-18,witheach
symbolindicatingthepresenceofthetaxoninaquarterdegreelatitudebyquarterdegreelongitudearea.
ThenumberofnamedannualspeciesrecordedforWesternAustraliasincethe publicationofthe
censusanditsmostrecentsupplement(Green1985,1988)hasincreasedbyseven. CurationofthePERTH
collectionbyKaren Wilsonhas ledtothe addition ofthetwo nativespeciesFuirenaincrassataand
IsolepisaustraliensisandtheintroducedspeciesIsolepishystrix. Afurtherfourspecies,namedsince
thelastsupplementofthecensus,areFimbristylissimulans(Latz1990),Schoenusbadius,S.plumosus
andS. variicellae(Rye 1997).
Onespeciespreviouslyrecorded(Wilson1981)forWesternAustralia,butnowexcluded,isIsolepis
platycarpa(S.T. Blake)Sojak. This species occurs in South Australia,New South Wales, Victoria,
TasmaniaandNewZealand,andmightprovetobemorewidespread,buttherearecurrentlynospecimens
knowntohavebeencollectedfrom WesternAustralia.
Thedescriptionsgivenforalltheannualspeciesincludedin“FloraofthePerthRegion"(Rye 1987)
areaccurateexceptthattheonegivenunderthenameSchoenusodontocarpusactuallyappliestothe
new species S. variicellae. At the time the flora treatment was prepared, no specimens of true
S. odontocarpusfromthe Perthregion had been seen, butsomehave sincebeen incorporated in the
collection at PERTH. Other newly recorded native species for the region are Isolepis congrua,
W
I. hookeriana, Schoenushumilis, S.plumosus, S. sp.Bullsbrook(././ Alford915)andS. sp. aroona
(G.J. Keighery 12235). Thereisalsooneadditionalnaturalizedspecies,Isolepishystrix.
B.L. Rye, Annual Cyperaceae from central and southern Western Australia 385
Figure 1. Distribution ofBulbostylis barbata in Western Australia.
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Figure 2. Full distribution ofBulbostylis burbidgeae+, and Western Australian distribution ofBulbostylis
turbinataO, atypical variant ofCyperuscastaneus and typical variant ofCyperus castaneus T .
B.L. Rye, Annual Cyperaceae from central and southern Western Australia 387
Figure 3. Western Australian distribution ofCyperusdifformis A and Cyperusrigidellus O.
388 Nuytsia Vol. 11, No. 3 (1997)
Figure 4. Western Australian distribution ofCyperus hamulosus+, Cyperus iriaO, Cyperuspygmaeus A
andCyperustenellus0
.
B.L. Rye, Annual Cyperaceae from central and southern Western Australia 389
Figure 5. Distribution ofCyperus squarrosus in Western Australia.
390 Nuytsia Vo!. 11, No. 3 (1997)
Figure 6. Distribution in Western Australia. A - Eleocharis atropurpurea; B - EleocharisgeniculataO and
Fimbrislylis ammobia .
B.L. Rye, Annual Cyperaceae from central and southern Western Australia 391
Figure 7a.ndWFeusitreernnaAnuusdtirfalloiraan •distarnidbutfiulolndoifsttryipbiuctailonvaorfiaanttypoicfalFimvbarriiasnttyloisfFdiempbaruipsetyrlaitsadeApau,pFeirmabtraistyVli,s velata
and Fimbristylis sp. ShayGap .
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Figure 8. Distribution in Western Australia. A - Fimbristylis littoralis\ B - Fimbristylis microcarya.