Four new Drosera taxa from south western Australia

10 Pages·1992·2.2 MB·English

by  Allen Lowrie

Nuytsia8(3):323-332(1992) 323
Four newDrosera taxa from south western Australia
AllenLowrie' and NevilleMarchant^
6
GlennPlace,Duncraig,WesternAustralia6023
^WesternAustralianHerbarium,DepartmentofConservationandLandManagement,
POBox 104,Como,WesternAustralia6152
Abstract
Lowrie, Allen and Marchant, Neville. Four new Drosera taxa from south western Australia.
Nuytsia8(3):323-332(1992).ThreenewspeciesandonenewsubspeciesoiDrosera (Droseraceae)
are described, D. browniana and D. stolonifera subsp. monticola (both tuberous Drosera) and
D. grievei and D. sargentii (both pygmy Drosera), all endemic to south western Australia. The
distinguishing characters ofeach arepresented as well as their relationships and an indication of
habitatpreferencesandconservation status.
Introduction
Thesouth westofWesternAustraliaisrenownedforitsrichnessofvascularplantspeciesandits
highdegreeofendemism. Fifty-fourspeciesofDroserawererecordedinAustraliabyMarchantand
George(1982);ofthese,42specieswerethenknowntooccurinthesouthwestofWesternAustralia.
Thenumberofspeciesnowknown tooccurin this region is 68.
Sincethepublication ofthefirsttwovolumesofCarnivorousPlantsofAustralia(Lowrie 1987,
1989),AllenLowriehas madeextensivefield studiesandhasdiscoveredanumberofnewDrosera
taxa. Aswellasextensivefieldstudies,hehaspropagatedandcultivatedallknownspecies. Neville
Marchanthasmade extensiveherbarium studiesincludingexaminationofalmostallDroseratype
specimens. In an endeavourtocombineinformation from thesevariedsourcesthepresentauthors
have collaborated tocircumscribeandpublish newtaxa.
Descriptions
1.Drosera browniana A. Lowrie & N. Marchant, sp. nov. (Figure 1)
Drosera bulbosa Hook, subsp. biilbosa affinis sed flore in statu fructificanti erecto, petalis
mm mm
obovatisapice truncato-crenato, extusroseis, intraalbis, 7-10 longis,4-6.5 latis.
Typus:0.9kmsouthoftherockcairnonHattersHillgoldmine,0.1kmwestoftheroadonthesummit
ofagraniteoutcrop, Western Australia,AllenLowrie99, 2/9/90 (holo: PERTH; iso: MEL,RSA).
324 NuytsiaVol.8,No.3(1992)
Figure 1.Droserabrowniana A.LowrieandN.Marchant
A-matureplantinflower,B-sepal;C-petal;D-ovarywithstyles;E-partofstyleandstigmas,enlarged;
F-leaflamina;G-T.S.ofleaflaminaasindicatedonF. Scalebarforall= 1mm
AllenLowrieandNevilleMarchant,FournewDrosera 325
Tuberousherb. Undergroundstem4-6cmlong. Leavesallinaflatbasalrosette;laminaobovate,
18 mm long, 10-12 mm wide; petiole7 mm long, 3 mm wide. Scapes 1-20,4-10cm long,single-
mm
flowered,erectin fruit. Calyx lobesovate, unitedatthebase, marginentire,apex serrate,4.5
long,2mm wide. Petalsdistallypink,proximallywhite,obovate,apextruncate-crenate,7-10mm
long,4-6.5mmwide. Ovaryovoid,1.5mmlongand 1.3mmindiameteratanthesis. Styles3,1 mm
long, branched repeatedly from near the base into numerous filiform segments, forming adense,
roundedtuft; stigmassubclavate.
Affinities.Droserahrownianapossessesatuberwithaverticalstolonwithprophyllsandarosetteof
f1l.atleaveswithabroadpetiole;stipulesareabsent. Thus,itbelongsinDroserasubg.ErgaleiumDC.
se2c.t. Erythrorhizae(Planchon) Diels.
3D..macrophyllaLindleyandD.bulbosaHook,anditssubspeciesaremorphologicallysimilarto
D. browniana. Thethreetaxacaneasilyandreliablybedifferentiatedbythecharacters which are
presentedin thefollowing synoptic key:-
Leaves oftherosette up to 12cm long at maturity
Scapes4-6-flowered; sepalsentire D. macrophylla
2. Scapes 1-flowered; sepals serrate D. bulbosasubsp. major
1.Leaves oftherosette lessthan 3 cm longat maturity
Stylesdivided; scapes erect in fruit; petalspinkand white;
flowers August-September D. browniana
3. Styles undivided; scapes secundin fruit;petals white; flowers
May-June D. bulbosa subsp. bulbosa
Distribution.Droserabrownianaisawidelyscatteredspeciesandisquitecommononsoilsassociated
withthenarrowgreenstonebeltfrom MtHolland(Lat. 32° lO’S,Long. 119°44’E),toHatters Hill
(Lat. 32°49' S,Long. 119° 59'E), adistance of85 km.
Habitatandphenology.Droserabrownianagrowsin smalldepressionswhicharefilledwithbrown
loamsoilonweatheredgraniticrockoutcrops. Theoutcropsaregenerallyonlyametreorsohigher
than the surrounding country and aie usually concealed in thickets of gimlet trees (Eucalyptus
species). Rainfall in thisregion is generally low andrestrictedto late autumn and winter (May to
August).
TheleavesofDroserabrownianaappearfromthetubersinJuneandfloweringoccursinAugust
andSeptember. In thedryperiodoftheyearDroserabrownianasurvivesasdormantunderground
tubers until theonsetofwinterrains.
Othercollections. WESTERN AUSTRALIA: Hatters Hill,intersection ofpipeline track and main
Hatters Hillbypassroad. Western Australia,Lat. 32° 49’ S,Long. 119°59’ E,PaulG.Armstrong,
24 Aug. 1990 (PERTH).
Conservation status.Arelativelywidespreadspeciesin nativebushlandeastofcultivatedareasand
notundercurrentthreat.
Etymology. This speciesisnamedafterAndrew Brown,an enthusiastofnativeorchidsandofficer
oftheDepartmentofConservation andLandManagementwho discovered the firstpopulation.
326 NuytsiaVol.8,No.3(1992)
2. DroserastoloniferaEndl. subsp. monticola A. Lowrie &N. Marchant,subsp. nov. (Figure2)
r)'pMi.SummitofToolbrunupPeak,StirlingRangeNationalPark,P.Marti;14/11/89 (holo:PERTH).
Drosera stolonifera Endl. subsp. compacta N. Marchant affinis sed stolonibus et tuberibus
hypogaeisin statumaturepersaepepraesentibus,caulispailehypoggaeis3.5 cm longis,stolonibus
adventitiisparum abbreviatis,petalisroseis usquead4 mm longis, ovarioelliptico.
Tuberous herbwith averticalstolon upto3.5 cm longwhichmaybranch toproduceadditional
terminaltubers. Abovegroundstemmoreorlesserect,2-7cmlong;leavesbasalandcauline,stem
usually notdevelopedin non-floweringspecimens. Basal leavesrosetted,laminaspathulate,4mm
long,6mm wide,moreorlessflat;petioleflattened,4mmlong, 1.5 to2mm wide,dilatedinupper
part. Caulineleavesusuallyscattered,rarelysub-oppositeorwhorled,laminaflabellate,5mmlong,
8mmwide,distinctlyconcave;petiole 10mmlong,1 mmwide,channelledabove. Flowersterminal.
Scapefew-flowered,5cmlong,glabrous;pedicels8mmlong. Calyxlobesunitedatthebase,ovate,
mm mm
4 long, 2 wide, lower margin entire, upper margin and apex irregularly dentate-crenate.
mm mm
Petalsobovate,8 long,5 wide,pale-pinkwithdark-pinkcloselyspacedflabellateveining.
Ovaryellipsoid, 1.3 mmlong, 1.2mm indiameteratanthesis. Styles3,0.8 mmlong,each divided
into many terete segments, half of them forming an irregular horizontally spreading whorl, the
remaindererect; stigmasterete.
Distribution. Droserastoloniferasubsp.monticolaiscommonon thesummitsofToolbrunupPeak
andBluffKnoll.ItislikelytooccuronthesummitsofotherpeaksintheeasternpartoftheStirling
Range.
Habitat.Restrictedtowintermoist,blackorbrownloamysoilsonledgesandinshallowdepressions,
often growing with moss. Only recorded from the upperslopes and summits which are frequently
cloud-coveredand are usually very moist.
Floweringperiod.OnlyrecordedforNovember. ThefloweringperiodisprobablybetweenOctober
andDecember.
Affinities. Droserastolonifera subsp. monticola belongs in subg. Ergaleium DC. sect. Stolonifera
DeBuhrbecauseitpossessesatuberand has leaves inabasalrosetteas well ascaulineleaves.
Droserastoloniferasubsp. compactaN. Marchantisconsidered tobe thetaxon mostsimilarto
Droserastoloniferasubsp.monticola. Theformersubspeciesoccursin heathlandfromtheStirling
Rangetothesouthcoastandcanbereadilyseparatedfromthenewsubspeciesbyitsflowercolour,
stolon morphology and petiole length. The morphological differences between the two taxa are
presented in thefollowingsynoptickey:-
1.Petalspink; additional below-ground stolonsand tubers
mm
often presentat maturity; petioles up to4 long; ovary
ellipsoid D. stoloniferasubsp. monticola
1. Petalswhite; additional below-groundstolonsandtubers
absent, thelowerstem prostrate; petioles 5-30mm long;
ovarysubglobose D. stoloniferasubsp. compacta
AllenLowrieandNevilleMarchant,FournewDrosera 327
Figure2.Droserastoloniferasubsp.monticolaA.LowrieandN. Marchant
A-matureplantinflower; B-maturenon-floweringplant;C-sepal;D-petal;E-ovarywithstyles;
F -partofstyleandstigmas,enlarged;G-caulineleaflamina; H-basalleaflamina; 1-T.S.ofcauline
leafpetioleasindicatedonG. Scalebarforall=1 mm
328 NuytsiaVol.8,No.3(1992)
Conservationstatus.RelativelycommonintheStirlingRangeNationalParkwhereitisapparently
notunderthreat.
Etymology.ThisnewsubspeciesisrestrictedtotheupperpartsoftheStirlingRangehencetheepithet,
monticola,referringtoitsmountain habitat.
3.Drosera grieve! A. Lowrie&N. Marchant, sp. nov. (Figure 3)
DroserapaleaceaDC. subsp.paleaceaaffinis sedscapo uno usquead 3 cm longo,5-10-floris,
mm mm
sepalisperlato-obovatis 2.5 longis, 2.5 latis.
Typus:AttheeastendofBaangaHillroad,nearthejunctionofSennettsLakeRoad,c. 20km east
ofLakeKing township.Western Australia,A Lowrie25/9/89 (holo; PERTH; iso: MEL).
Fibrousrooted herbforming acompact convex rosetteto 1.2 cm diameter. Stem to2 cm long,
coveredwiththewitheredremainsofthepreviousseasonsgrowth. Leaves20-30. Laminaorbicular,
subpeltatc,0.7 mm diameter;petiole3.6mm long,0.5mm wideattheba.se,dilatedto0.8mm wide
inthelowerpart,0.2mmwideattheapex. Stipulebudovoid,3mmlong,2mmdiameter,withsetae.
mm mm
Stipules3-lobed,5 long,4 wide;thecentrallobedividedinto2segments,eachsegmentin
turn divided into two segments narrowing tosetae, lateral lobes with ashortsegment on theouter
marginnearthebase,andtwoasymmetricallybifurcateapicallobes. Inflorescenceracemose;scape
1,to3cmlong,coveredwithminuteshortbroadglands;flowers5to 10;pedicels2.5mmlong,semi-
erectinfruit. Calyxlobesverybroadlyobovate,unitedatthebase,2.5mmlong,2.5mmwide,apex
mm mm mm
irregularlydentate. Petalswhite,oblong,4.0-4.5 long,2 wide.Ovaryturbinate,0.7 long,
1mmdiameteratanthesis.Styles4,spreadinghorizontally,0.5mmlong,0.1 mmdiameter;stigmas
mm mm
falcate, 1.2 long,0.15 diameter,apex subacute. (Figure 3)
Distribution. Known only from two locations, 30 km apart, in the eastern wheatbelt south-eastof
Hyden.
Habitat. Inclayey sandon heathland underand between low shrubs.
Affinities. D. grievei belongs in Drosera subg. Rorella (DC.) Diels, sect. Lamprolepis Planchon
because it has rosetted leaves, prominent stipules, many-flowered scapes and it reproduces by
propagules. D.paleaceaDC. subsp.paleaceaisconsideredtheclosestrelativeofDroseragrievei
butdiffersfrom it in thefeaturespresented in the synoptickey below:-
1. Scapes 5-10-flowered; sepals very broadlyobovate, 2.5 mm
mm mm
long, 2.5 wide. Petalsoblong,4-4.5 long D. grievei
1. Scapes 30ormore-flowered; sepalsobovate, 1.5 mm long,
mm mm
0.7 wide. Petalsobovate, 3-4 long D.paleacea subsp.paleacea
Conservationstatus.Threatened. Currentlyknownfromonlytworoadsidelocations inanareawhich
hasbeen extensivelycleared forfarmland.
AllenLowrieandNevilleMarchant,FournewDrosera 329
Figure3.Droseragrievei A.LowrieandN.Marchant
A-matureplantinflower; B-sepal;C-petal;D-ovarywithstyles;E-partofstyleandstigma,enlarged.
F-leaflamina;G-T.S.ofleafpetioleasindicatedonF. Scalebarforall=1mm
330 NuytsiaVol.8,No.3(1992)
Etymology.Droseragrieveiisnamedin honorofBrianJamesGrieve(1907-),ProfessorEmeritus,
who has provided theonlycomprehensivemeansofidentifying therich floraofsouthern Western
Australia. From 1954ProfessorGrievehasproducedtheoutstandingseriesofbooks"HowtoKnow
Western Australian Wildflowers".
4. Droserasargentii A. Lowrie & N. Marchant, sp. nov. (Figure4)
Droseraparvula Planchon affinis sed stipula-gemma conicis, 6 mm longa, 4 mm diam., setis
longissimisdenseobtectis.
Typus: At thejunction of Stockyard Road and Merivale Road, in the S.E. corner, c. 20 km E of
Esperance, Western Australia,A//c/iLowrie22/11/89 (holo: PERTH; iso: MEL).
Fibrousrootedherbformingacompactconvexrosetteupto 1.5cmdiameter. Stemto2cmlong,
coveredwiththewitheredremainsofthepreviousseasonsgrowth. Leaves20-50. Laminaorbicular,
mm mm mm
almostpeltate,0.8 diameter;petiole 3.8 long,0.5 wide from thebaseforathirdofthe
mm mm mm
length,theupperpart0.2 wide. Stipulebudconical,6 long,4 diameter,withextremely
mm mm
longsetae. Stipulesshortly3-lobed, 1.5 long, 1.7 wide,lobestruncate,thecentrallobewith
mm
5 shortfringes,thelaterallobes with 3 shortfringesanda5 longsetaadjacenttothe mid-lobe.
Inflorescenceracemose; scapes 1 to 2, up to 5 cm long,glabrous; flowers 20to40; pedicels 1 mm
mm mm
long,pendulousin fruit. Calyxlobesglabrous,ovate,unitedatthebase,1.5 long,0.9 wide,
mm mm
margin entire,apex slightly serrate.Petals white, obovate, 3 long,2 wide, entire. Ovary
mm mm mm
obovoid,0.4 long,0.5 diameteratanthesis. Styles 3. while,semi-erect,0.3 long,0.1
mm mm mm
diameter; stigmas while,falcate-clavate, 1.1 long,0.1 diameteratthebase,dilated to
mm
0.15 diameternear theroundedapex.
Distribution. Droserasargentiiisacommon species in thecoastalregionsbetween Esperanceand
CapeLe Grand NationalPark.
Habitat. Indeep,whilesiliceoussoilonheathland. Atmanylocationsitgrowswiththewidespread,
white-flowered speciesDroserascorpioides.
Floweringperiod. November-December.
Affinities.D.sargentiibelongsinDroserasubg.Rorella(DC.)Diels,sectionLamprolepisPlanchon
because it has rosetted leaves, prominent stipules, many-flowered scapes and it reproduces by
propagules. D.pan’ulaPlanchonisconsideredheretobespeciesmostsimilarXoDroserasargentii.
Thetwo taxadifferin thefeaturespresented in thefollowing synoptic key;-
1. Stipulebud formingaconicaltuft,densely covered with extremely long
setae; pedicelspendulous in fruit; sepals 1.5 mm long; petals3 mm long D. sargentii
1. Stipulebud formingan ovoid tuft, with short setae covering the lowerpart
andlongsetae attheapex; pedicels semi-erect in fruit; sepals 3-4 mm long;
mm
petals4-6 long D.parvula
Conservation status. A common andapparently widespreadspecies notundercurrentthreat.
AllenLowrieandNevilleMarchant,FournewDrosera 331
Figure4.Droserasargeiitii A.LowrieandN. Marcliant
A-matureplantinflower;B-sepal;C-petal;D-ovarywithstyles;E-partofstyleandstigma,enlarged;
F-leaflamina;G-T.S.ofleafpetioleasindicatedonF. Scalebarforall=1mm
332 NuytsiaVol.8,No.3(1992)
Etymology. Drosera sargentii i.s named in honour of Oswald Hewlett Sargent (.1880-1952), a
PharmacistofYork, WesternAustralia,whomadeamajorcontributiontoWesternAustralianbotany
including studieson thegenusDrosera.
ThisnewspeciesofpygmysundewwasdiscoveredbyAllenLowrieandSteveRosein1988when
ithadjustfinishedflowering. The following season, flowering specimenswerefoundandbrought
intocultivation forcloserstudy.
References
Lowrie,A. (1987). CarnivorousPlantsofAustralia. Volume 1. (UniversityofWesternAustraliaPress,Nedlands,Western
Australia.)
Lowrie,A. (1989). CarnivorousPlantsofAustralia. Volume2. (University ofWesternAustraliaPress,Nedlands,Western
Australia.)
Marchant,N.G. (1982). Droseraceae.InGeorge,A.S. (ed.)FloraofAustralia. Volume8:383-385. (AustralianGovernment
PublishingService,Canberra.)