THE GENUS PRENANTHES (ASTERACEAE: LACTUCEAE) IN TEXAS

2004·4.5 MB·English

by  Jason R Singhurst

THEGENUSPRENANTHES(ASTERACEAE:LACTUCEAE)
INTEXAS
Jason R.Singhurst RobertJ.O'Kennon
WildlifeDiversityProgram BotanicalResearchIristituteofTexas
TexasParksandWildlifeDepartment 509PecanStreet
Austin,Texas78704,U.S.A. FortWorth,Texas76102-4060,U.S.A.
WalterC.Holmes
DepartmentofBiology
BaylorUniversity
Waco,Texas76798-7388,U.S.A.
ABSTRACT
ThreespeciesofPrenanfhesoccurinTexas.PrenanthcscarrhSinghurst,O'Kennon.&Holmesisde-
scribedasanewspeciesendemictotheEdwardsPlateauvegetationalregion.Prcnanthesaltissimais
knownonlyfromjasperandNewtoncountiesinextremesoutheasternTexas.Prenanthesharhatais
morewidespreadbutrareinrichhardwoodandpme-oakforestsinthePineywoodsofeasternTexas,
withonerecordmthePostOakSavannahofLamarCounty.Akeytospecies,descriptions,distribu-
tionn^ap,andlistsofexsiccataeareincluded.
RESUMEN
EnTexashaytresespeciesdePrencmi/ics.SedescribePrenanthescarriiSinghurst,O'Kennon,&
HolmescomoespecienuevaendemicadelaregiondevegetaciondeEdwardsPlateau.Prenanlhes
altissimaseconoceunicamentedeloscondadosdeJasperyNewtonenelextremosurestedeTexas.
Prenanthesharhataesmasfrecuenteperoraroenlosbosquesdemaderaduraydepino-robleenlos
pinaresdelestedeTexas,conunacitaenlasabanadePostOakdelcondadodeLamar.Seincluyeuna
clavedeespecies,descripciones,mapasdedistribucion,yhstasdeexsicatas.
INTRODUCTION
CorrellandJohnston(1970)recognizedtwospeciesofPrcnanthesL.inTexas.
Oyenaer,fP.raolmtitshseimsaamL.ewlaoscaitdieonntinfiieNdefwrtoomntChroeuentsyp.ecPirmeennasntahlelscohlalrehcatetdat(hT.e&saGm.e)
MilsteadexCronquistwasidentifiedfromtwospecimens,oneeachfromjas-
perandNacogdochescounties.By1993knowledgeofthegenusinTexaswas
baseduponsevenadditionalcollectionsofP.harhataandtwoadditionalcol-
lectionsofP.altissima.In1993and1994Singhurst(1996)conductedastatus
surveyofP.harhatainTexasthatincreasedtheunderstandingofitsdistribu-
tionandhabitatrestrictions.Thatsurveypromptedthepresentexpandedstudy
Thepurposeofthepresentpaperisto(1)describeanewspeciesof
PrenanthesfromtheEdwardsPlateauvegetationalregionofTexas,(2)report
theadditionalinformationregardingtheTexasdistributionofP.altissimaand
P.harhata,(3)provideakeytodistinguishthethreespeciesinTexasand(4)
SIDA21(1):181-191.2004
182 BRIT.ORG/SIDA21(1)
remarkontherarityandabundanceofallspeciestreated.Fieldresearchand
collectionsmadebetween1993and2003formtheprimarybasisofthisstudy
ThemajorityofspecimenscollectedaredepositedintheBaylorUniversityI]er-
barium(BAYLU).OtherspecimensfromASTC,BRIILAMU,RiceUniversity
Herbarium,HoustonTexas(hereaftercitedasRICE),SBSC,TAES,TAMU,TEX-
LL,US,andthepersonalherbariumofSteveOrzellandEdwin Bridgeswere
examinedandannotated.
CultivationstudiesofbothP.harbaUi(1993-1994)andP.allissima(1998)
were conductedat theStephenEAustinArboretumand Tucker Estate,
Nacogdoches,Texas.Thenewspecieswascultivatedm2003attheresidenceof
O'KennoninEortWbrth.Thoughhmited,thesecultivationstudiesprovided
growth)forminlormationthatwasotherwiseunavailable.
TAXONOMICTREATMENT
PrenanihesL,Sp.Pi.797-798.1753.
NuJw/u.sCass.,Did.Sc,Nat.34:04,1825.
Perennialherbswithmilkyjuiceandtuberousroots.Leavesalternate,simple
andentiretotoothedtofew-lobedordeeplycleft,orloweronessometimessev-
eral-foliate.Capitulamostlynumerousinanelongate,erectandoftennodding
paniculiformcapitulescence;flowersligulate,perfect,5-15mnumber,white,
yellow-white,togreenish-white;involucrescylindric,of4-8principalphyllar-
ies,theouterphyllaries(bracts)muchreduced;receptaclesepaleate.Cypselae
cylmdricornearlyso,glabrous,mostlyreddish-brown,multicostate;pappus
ofnumerousdeciduouscapillarybristles.
Prcnanthesisagenusofapproximately40species(Rao&Datt1996)with
apredominantlynorthtemperatedistributionexceptforonespeciesofsouth
centralAfrica(Milstead1964).Twosubgeneraarerecognized.SubgenusNahalus
includesallspeciesofNorthAmericaandnortheastAsia,whiletheEuropean
andAfricanspeciesareinsubgenusPrcnanthes.Classificationofthegenusis
complicatedbyfrequenthybridizationandbyextrememorphologicalvaria-
tion(Cronquist1980).
Plantsofthegenusarecommonlyknownasrattlesnakeroot,cankerweed,
orgalloftheearth.ThenamePrenanthcsisfromGreekprenes(drooping)and
anthc(ilower).Thisnamereferstothenoddinghabitofthecapitula.
KEYTOTHESPECIESOFPRENANTHHSINTEXAS
1. Capitula5-6flowered;involucreswith5-6principalphyllaries,glabrous P.altissima
1. Capitula10-15flowered;involucrewith6-8principalphyllaries,pubescentwith
longcoarsehairs,
2. Lowerandmidstemleavesshallowlyordeeplypinnatelylobed,theupperlan-
ceolatetooblong;petiolesusuallyshorterthantheblades;capitulescencerace-
nnosetoslightlypaniculate . p.barbata
SINGHURSTETAL,ANEWSPECIESOFPRENANTHESFROMTEXAS 183
2. Lowerandmidstemleavessagittiform,theupperovatetotriangular-deltate;
petiolesusuallylongerthantheblades,capitulescensepaniculate P.carrii
PrenanthesallissimaL.,5p.Pi.797.17.53.NahalusaltissimusiL.)Hook.,Fl.Bor.Amer.
1:294.1833.Type;LINN;IDCmicroriche177.536.III.1.
Prenanthc'iallisiimaL.vancinnamomeaFern..Rhodora10:95.1908,Tvrn:U.S.A.MISSOURI:
Monteer,5Oct1905.Bush.3.5.34(ilOLOTYPE:GH).
Perennialherbsfromathickandknottyconn-liketaproot.Stemserectto200
cmtall,glabrous,striate,theupperportionsnotbranchedorrarelyso,leafy
towardsthebaseandsparsetoleaflessintheimmediate vicinityof the
capitulescence.Leavesovatetotriangular,3-5lobed,2-14x1.5-12cm,thelower
onessometimeswitheredbeforeanthesisbutcanalsobepresent;venationpin-
nate,with4-6pairsofprominentsecondarynervesseparatingfromthemidvein
atanangleofca.45°,thenervesarcuate,tertiaryandquartenarynervesreticu-
late,surfacesglabroustovi1lous;baseswidelycordatetoanobtuseinsertionat
thepetioles,marginsdentate,theteeth0.5-1cmdistant,apicesacutetoacumi-
nate;petioles0.5-8.5cmlong,winglessthroughoutitslength;upperleavesre-
ducedmsize;deltoidtoreniform,shortlypetiolate,marginsslightlydentate.
Capitulescenepaniculate,headsdisposedinlooseaxillaryclustersinupper
axils,20-28cmtall.Capitulaslender,12-15mmlong;pedunclesto2-3mm
mm
long,puberulent;bracts(outerphyllaries)lanceolatetoovate,1-2 long,
apicesacuminate,marginspuberulent;primaryphyllanes5,10-12mmlong,
lanceolate,greentolilac,apicesacuminate,glabrous.Floretswhite,5-6innum-
ber,10-11mmlong,tubesca.6mmlong,ligules5mmlong,5-nerved,teeth5,
mm
linear,sparinglyglandular,surfacesglabrous,anthers4 long;stigmatic
mm
surfacesdenselyhispidtosetose.Cypselaeobscurely 5-angled,5 long,
golden-brown.Pappusbristlesca.40-50,yellow-brown,ca.8-9mmlong,mar-
ginsfinelyscabrid.
Disfj'ibution.—KnownonlyfromJasperandNewtoncountiesinextreme
southeastTexas(Fig.1);alsoQuebectoMaine,StoGeorgia,Tennessee,Kentucky,
Arkansas,andLouisiana.
Phenology—FloweringfromlateAugustthroughOctober
Specimensexamined.TEXAS.JasperCo.:SallyWithersLakearea,Autumn1974,Watsons.n.(RICHJ
NewtonCo.:FR1414about3miSEofBurkeville,23Mar1969,CorrcU.36864(TEX-LLj:FR1414
about3miSEofBurkeville.15Oct1969,Correll38172(TEX-LL);FR1414,about3miSEofBurkcville,
29Oct1969.Condi&Condi38217(TEX-LL);ScrappmValley,25Oct1974,Walsons.n-Scrappm
ValleyPreserve,TempleInlandProperty,12miNNEofBurkeville,2Aprf998,Singhurst&Watson
6.548(BAYLU):jci.FM645andHickmanCreek,WonHickmanCreek0.4mi,3Apr1998,Singburst&
Watson6559(BAYLU);CanyonRimTrail,Tex.Hwy87,0.5miNofMayflowerCommunity,30Sep
2001,Holmes11997&Singhurst(BAYLU);LouisianaPacificCorp.NatureTrail,4miNofjet,ofTex.
Hwy87andR255onHwy87,23Sep2003,Singhurst12494(BAYLU):Tex.Hwy87,2,1miSofjet.
withTe.x,Hwy63,SEonCo,Rd,2,7mitoSimmsCemetery,YellowBayoublulfsandbanks,23Sep
2003,Singhurst12494(BAYLU).
184 BRIT.ORG/SIDA21(1)
,
Fig.1.DistributionmapofthegenusPrenanthesinTexas.PrenanthesaltissimaM,P.barbata andP.carrii<
Prenanlhcsaltissimaisknown1romsevenlocationsmthenorthernportionof
JasperandNewtoncounties.TheselocationsarethesouthwesternlimitofP.
flitissima'sdistributioninTexas.OutsideTexas,thenearestdocumentedoccur-
rencesareapproximately120kmdistantinEvangelineandRapidesparishes,
Louisiana(Thomas&Allen1996).ThenearestArkansaspopulation(Smith
1979)isabout320kmdistant.InTexasthespeciesoccursonprimaryandsec-
ondaryterracesalongstreambanksofsmallperennialspring-fedcreeksand
bankso( largerstreamswith Ilood plainsthatsupporthardwood forests.
PrenanthesaltissimaISiissociatedwiihb'agusgrandifoliaMagnoliagrandiflora,
Acerharhatum,Quercusalba,Hamamelisvirginiana,Rvernalis,Linderaben-
zoin,Liliummichauxii,lipulariadiscolor,Sanguinanacanadensis,Polygonatuu]
biflorum,Polysiiihumairostichoides,Thclypterishexagonoptera,Trilliumgrac'
He,Spigeliamarilandica,Solidagoauriculala,andS.caesia.
SINGHURSTETAL.,ANEWSPECIESOFPRENANTHESFROMTEXAS 185
Cronquist(1980)recognizedtwovarietiesofPrenanthesaltissima,var
altissimawithwhitishtopalebrownpappus,occupyingthegreatestpartol
thedistributionofthespecies,andvarcinnamomeaoiMissouri,Arkansas,Loui-
siana,and,thoughnotcitedbyCronquist,presumablyTexas.Thisvarietyis
characterizedbybrightyellow-brownoralmostorangepappus.Gandhiand
Thomas(1989)usedthisvarietalnametorefertotheLouisianaformsofthis
taxon.However,ThomasandAllen(1996)mergedvarcinnamomeawithvar
altissimaintheAtlasoftheVascularFloraojLouisiana.Colorvariationofthe
pappusdoesnotappeartojustifyrecognitionatthevarietallevel.
Prenanthesbarbata(Torr&A.Gray)W.L.MilsteadexA.Cronquist.Brittonia
29:223.1977.NahalusfraseriDC.var.harhatusTorr.&A.Gray,Fl.N.Amer2:481.
1843.PrenanthesserpentariaPurshvarharbata(Torr&A.Gray)A.Gray,Syn.Fl.
N1:.8.A1m9e00r.1N(a2)h:a4l3u4s.s1e8r8p6e.nNtaahriaaluPsurhsahrhvaatrush(aTrohrartu&s(AT.oGrrra&y)AH.elGlrera,y)MuMholhern,bCeorngtira
U.S.Natl.Herb.6:755.1901.TYPE:U.S.A.ALABAMA:Buckleys.n.(syntype:GH;
ISOSYNTYPE:NY).TheGHspecimenisheredesignatedaslectotype.Theother
syntypecited,Machride.s.n.IromtheSaludaMountainsof[PolkCo.,NorthCaro-
lina],wasnotlocatedbuttromlocationseemstoretertoP.serpentariaPursh.
Perennialherbsfromthickcorm-liketaproots,occasionallyconnectedbyslen-
derrhizomes.Stemserect,50-150cmtall,simplebelow,glabrous,theupper
portionsoftenbranched,glabratetopilosetohispidtosemiarachnosetovil-
lous,leafyexceptintheimmediatevicinityofthecapitulescence.Leavesoblan-
ceolatetospatulate,5-20x 1.5-5cm,theloweronesusuallywitheredbefore
anthesis,venationpinnate,with4-6pairsofprominentsecondarynervessepa-
ratingfromthemidvematanangleofca,45degrees,thenervesstraightto
arcuate,tertiaryandquartenarynervesreticulate,surfacesglabratetosparingly
puberulent-pilose;basesattenuate,thelowertolongwingedpetioles,margins
entiretodenticulatetodentatetolacerate-parted(especiallylowerleaves),the
teeth1-2cmdistant,apicesacutetorounded;petioles0.5-6.5cmlong,winged
formostofitslength;upperleavesreducedinsize;elliptictooblanceolate,sessile
toshortlypetiolate,marginsmostlyentiretodenticulatetolesscommonlyden-
tatetolacerate-lobedatthebases.Capitulesceneracemosetopaniculate,5-36
cmtall.Capitulacylindrictosemicampanulate;pedunclestoca.1cmlong,
glabratetotomentosetovillous;bracts(outerphyllaries)lanceolatetonarrowly
ovate,2-5mmlong,apicesacuminate,marginssubentire,midribswithlewto
numerouscoarsebristles;primaryphyllaries6-8,13-16mmlong,linear-ob-
longtonarrowlylanceolate,greentopurplish,apicesacutetoroundedtoan
acutepoint,finelypuberulent,occasionallywithglandularhairs,marginsen-
tire,midribswithfewtonumerouscoarsebristles.Floretswhite,10-12innum-
ber,12-13mmlong,tubesca.5-6mmlong,ligules5-6mmlong,5-nerved,teeth
mm
5,linear,sparinglyglandular,surfacesglabrous,anthers5-5.5 lmonmg;stig-
maticsurfacessetose-hispid.Cypselaeobscurely5-angled,5-5.5 long,
!
18ii BRIT.ORG/SIDA21(1)
golden-brown.Pappusbristlesca.50,whitetoyellow-brown,ca.8mmlong,
marginsscabrid.
Distribution.—EasternTexasfromHardinCountynorthtoLamarCounty
(Fig.1);alsoAlabama,Arkansas,Georgia,Kentucky,Louisiana,andTennessee.
PhenoZog}'.—FloweringfromlateAugustthroughNovember.
Specimensexamined.TEXAS.AngelinaCo.:Comp.94,AngelmaNationalForest,ca,0.7miSoijunc-
tionofFSRd303andFSRd302onFSRd303,jet.ofFSRd303andBigCreek.11Nov1994,Smghurst
3609(BAYLU).CassCo.:ca.0.4airmiSWoljct.ofTe.x.Hwy11andTex,Hwy8ati.inden,240ct
N19o9v4,1S9i9n4,ghSuirnsgth3ur4s0t43(6B1A0YL(UB)A.YLCUh)e.roHkaerediCno.C:o.c:a.W0.5saiidremoilSSiElsobleejet.neoalrU.MSi.llHCwryee6k9,aRndd3F27M,22421,Se1p7
1971,Watson766,767,&r768(RICE);WoiSilsbeeonTex,Hwy327nearMillCreek,29Sep1971,
Amerson806(SMU).JasperCo.:U.S.Hwy96,ca.2.0miSofJasper,10Oct1946,Lundell&Lundell
14674(TEX);ca.3.5miSWofJasperonFM777,4Nov1982,Agi!v,sgi8270(TAMU);SofWalnutRun
CreekonU.S.Hwy96,1.8miSofjct.U.S.Hwy190and96inJasper,29Oct1993,Singhurst3401
(BAYLU);roadsideparkca.1.6miSolU.S.Hwy190and96mJasper,13Oct1982,Cheathams.n.
(TEX).LamarCo.:FM906,1.4miEoljct.olFM906andUS,Hwy271atMidCity18Oct2002,
S11m93ii97n33Eg,Sh(CuFTaErorsXftr)&,W1i31Hn23at47re62rri((sTHSiEMlXUil-,).L;H1L.9T)59e;(4xB,.LAi1YHt4LtwlUOeyJc.Lt2oN11ca,9oc91o3B0,ga0dySyooiaucn,rhgdhecsuas.rWCs9ot..0o:3fm4ciL0ao6W8c(oBoABlmaYiNyLaoUNuc)E,o;gcocalda.o.N0ca1.h.c49eo5smgmidoionEcWhToeefxso.C.foHj.4cwtOR.ydco,tf2811E2,99M4c.1a.9225P1.a1aOranckidtsr
FM1878,5Sep1994,Singhurst3407(BAYLU);ca.9.2miNNEofNacogdochesonU.S.1Iwy59,4.5mi
SSWofGarrisononU.S.Hwy59,1Nov1993,Singhursts.n(BAYLUJ;ca.4.2miNEofjci.olLoop224
aSminindgNhEWuMrsf1t8r7o38m60ij1cnt.N(oaBfcAYoU.LgSUd.)o;HchwNeyasc5oo9gndaFoncMdhe1Fs8M7,8,3W4C3aeronrnidzFooMfEsS3tpa4rt3ei,snc,ga.5VS0a.el9plea1iy9r9lm4O,iriSvEeiS,nEg5ho.ufSerWpsit1n39t49e04r8,(HSiBilAlnY,gLh5uUSr)es;ptc1a3.969604.2,9
(BAYLU);BranchenteringintoBarnesLake,ca.1.5airmiSWofBarnesLakeDam,5Sep1994,Singhurst
340.5(BAYLU).NewtonCo.:jct.ofClearCreekandU.S.Hwy190.7Mar2002,Singhurst11202(BAYLU).
PolkCo.:MorganCreek,EM1988,2.6miSWofjct.Tex.Hwy146andFM1988,27Sep1994,Singhurst
3403(lUYI.U).RuskCo.:ca.2.5airmiNNEofjct.olTex.Hwy322andU.S.Hwy259,NofHenderson,
24Oct1994,Singhurst3402(BAYLU).SabineCo.:Comp.66,SabineNationalForest,MatlockHills,
ca.4.4miNEoljct.ofTex.Hwy21andEM3153,14Aug1994,Singhurst3606(BAYLU);Comp.69,
SabineNationalForest,ca.1.3miEofjct,ofFSRd131andFSRd131-AonFSRd131-A.ca.2.1airmiS
oljct.ofUS,Hwy87andFSRd131,14Aug1994,Singhurst3607(BAYLU);Comp.72,SabineNational
Forest,ca.3.4mifromjct.olTex.Hwy21andU.S.Hwy87,ca,0,3airmiSWolRedHillsLake,14Aug
1994,Singhurst3608(BAYLU);Tex.Hwy21.5.9roadmiEoljct.FM225atDouglass,12Oct1993,Carr
13246(TEX-LL).SanAugustineCo.:Comp65.SabineNationalForest,ca,0,8mionFRthatenters
Comp,65IromW,14Aug1994,Sing/iur,s(3604(BAYLUJ;ca,3.5airmiNNEofjct.olAttoyacRiver
aWnNdWTex.ofHSwaynA2u1,gu1s4tiAnueg,129994S,epSi2n0g0t1i,urHstol3m6e0s5&(BASYiLngUh)u;rsStpr1i1n9g70Ri(dBgAeYLoUn),ArSehneolsbayCCroe.:ekS,acbai.ne12Nmai-
tionalForest,TenahaRD,Compartment51,ca,1.4airmiNNWofjct.olFM1279andTex.Hwy147,
14Aug1994,Singliursf3400(BAYlJJj;Comp,51.SabineNationalForest,ca.2.2mifromjct.ofFM
1279andFM147onFM147,22Apr1987,Orzell&s:Bridges3126(pers,herb.J.
ThedistinctnessofPrenanthesharhatawasfirstrecognizedbutneverformal-
L'redbyMilstead(1964).ThenamewassubsequentlyadoptedbyCorrelland
Johnston(1970)andgainedgeneralacceptance;itwasformalizedbyCronquist
in1980.
SINGHURSTETAL.,ANEWSPECIESOFPRENANTHESFROMTEXAS 187
ThespecieswasconsideredrarebyCorrellandJohnston(1970)becauseit
wasknownonlyfromJasperandNacogdochescounties.Turneretal.(2003)
presentedanexpandeddistributionineastcentralTexasthatincludedsixcoun-
ties.Turneretal.alsousedthenametorefertoplantsoftheEdwardsPlateau
which,inthisstudy,areconsideredadistinctspecies.Prenanthesharhataoc-
cursinmesicravineslopeforeststhataredominatedbyFagusgrandijolia-
Quercusalhaseries(Diamondetal.1987)andonmesichardwoodsiteswith
Quercusshumardii,Q.muhlenhergix,Q.alha,Q.michauxii,Pinustaeda,Carya
ovata,andC.myristicaeformis.
PrenanthescarriiJ.R.Smghurst,RJ.O'Kennon,&W.C.Holmes,sp.nov.(Fig.2).
Type:U.S.A.TEXAS.BanderaCo.:LostMaplesStateNaturalArea,aboveandbe-
lowUpperForksofMysticCanyonTrail,1Sep2003,Singhurst&Singhurst12496
(holotype:BAYLU),
AF.harhataesimilisseelfoliissagittilormibusdiffert.
Perennialherbsfromtuberoustaprootswithsimilarsideroots.Stemssimple,
erect,occasionallyratherlongbranchedinareaofinflorescence,80-150cm
long,strigosetotomentoseinupperhalf,scatteredstrigosetoglabrousbasally.
Lowerleavessagittiform(ovate,ovate-deltatetobroadlyellipticmgeneralcon-
tour),13-25X7-12cm,lightgreen,chartaceous,venationpinnate,with3-5pairs
ofprominentsecondarynervesseparatingfromthemidveinatanangleofabout
45degrees,nervesstraighttoslightlyantrorselycurved,tertiaryandquartenary
veinsreticulate;surfacesglabratetolightlypuberulent-setoseespeciallyon
nerves;basesattenuate,truncatetowidelycordate,occasionallydeeplypin-
natelydividedatbasenearpetioles,marginscoarselyandirregularlydentate,
mostly1-2cmdistant,teethsubspinose-mucronate,apicesacutetorounded;
petioles2.2-13cmlong,broadlywingedforhalformoreofitslengthbythe
decurrentleafbases;upperleavesreducedinsize,elliptic,occasionallynearly
sessileorwithwinged-decurrentpetiolestoabout1cmlong,otherwisesimilar
tolowerleaves;bractealleavesreducedinsize,lessprominentlydentatetooc-
casionallysubentire.Capitulescencepaniculate,20-50cmtall;capitulacylin-
drictosemicampanulate;peduncles,4-9mmlong,tomentulosc,with5-12or
morelinear-subulatetonarrowlylanceolatehispidbracts(outerphyllaries)2-
4mmlong;primaryphyllaries8,9-11mmlong,mostlylimegreentopinkish-
rosetolavender,linear-subulatetolanceolate,apicesacuminate,outersurfaces
glabrateexceptforthesparinglyhispidmidrib,apicalmarginsminutelycili-
ate.Florets9-11percapitulum;11.5-13.5mmlong,tubes4-7mmlong,ligules
ca.7mmlong,5-nerved,teeth5,linear-oblong,0.07-0.1mmlong,apicalsur-
facespapillate;anthersca.5.5mmlong;stigmaticsurfacesdenselyhispid-se-
tose.Cypselaeirregularlyangledtomoreoftenterete,ca.6.3mmlong,golden
yellowtotan,prominently12-15costate.Pappusbristleswhitetotantoyellow,
7-8mmlong,30-40,marginsscabrid.
188 BRIT.ORG/SIDA21(1)
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Fig.2.Prenanthescani'r.A.habit,B.upperbractealleaves,C.middleleaf,D.basalrosetteleaf,E.florets,F.pappus,G.
matureacheneandH.immatureachenewithligule/antherdetail.IllustrationbyLinnyHeagy2004.Specimensusedin
illustrationincludeacombinationofSinghurst&Singhunt12496(BAYLU)andO'Kennons.n.(BAYLU).
SINGHURSTETAL.,ANEWSPECIESOFPRENANTHESFROMTEXAS 189
Distribution.—SouthwestEdwardsPlateau(Bandera,Gillespie,Kerr,and
Realcounties)ofTexas(Fig.1.)
Phenology—FloweringlateAugusttoNoveinber
Par.atyphs:TEXAS.BanderaCo.:LostMaplesStateNaturalArea,UpperCanCreek,17Nov1999.
Singhurst8.53,3(BAYLU);t.oveCreekPreserve,TheNatureConservancyofTexas,2Nov2002,
Singhursl)1544(iiolotyi'1::BAYLUj.GillespieCo.:7miNo(HarpermrichcreekcanyonotfThrcadgill
Creek,Oct1993,0'KennonJJ9J4(TEX-LLj.KerrCo.:alongrockyspringbranch,Lacey'sRanch,3Oct
1916.Palmer1089:](US);withoutspecificlocation,13Oct1940,Parkis.n.(TAES);12miSofKerrville
alongLambCreek,Oct1993,0'KennonII898(TE.X-LLJ;5.3miNofjet.ofKerr/BanderaCountyline
onTex.Elwy16,UpperLambCreek.17Nov1999,Singhurst8534(BAYLU);cultivated[propagules
fromUpperLambsCreek],18Oct2002.CrKennons.n.(BAYLU).RealCo.:LostMaplesStateNatural
Area,27Oct2001,Singhurst11526(BAYLU);upperreachesofMillCreek,GreyW'bllcRanch,2Nov
2002,SinghurstU554(BAYLU),
PrenanthescarriiismorphologicallysimilartoP.crepidineaMichx.,P.alata
(Hook.)D.Dietr,P.sagitUiia,(A.Gray)A.Nels.,P.hootw(DC.)D.Dietr,andP.
harhaia.ThisgroupwasproposedasanewsubsectioninMilstead's(1964)un-
published(thusneverformalized)dissertation.Thegroupischaracterizedby
paniculatetoracemosecapitulescences,leavesatleastshortpetiolate,flowers
whitetocreamyandusuallynumbering7-38percapitulum,innerphyllaries
6-15,andouterphyllaries(bracts)mostly7-13percapitulum.Lealcharacter-
isticsofP.carriiresemblethesagittiformshapedleavesofP.alata,P.crepidinea,
andP.sagittata.ThenewspeciesappearstobemostcloselysimilartoP.harhata,
particularlyinthepaniculatenatureofthecapitulescence.Thetwospeciesmay
bedistinguishedbythecharactersreferencedinthekey.Additionaltraitsdis-
tinguishingP.carriifromP.bflrbataincludeitstallerheightof80-150cm,stri-
gosetotomentosevestiture,andprimaryphyllaries9-11mmlong.Prenanthes
harhataisusually55-125cmtall,hastomentulosetosubarachnosevestiture,
andhasprimaryphyllaries11-14mmlong.
Prenanthescarnioccursprimarilyinrichsoilsinwoodlandsattheupper
reachesofcanyonswherespringsflowduetogeologiccontacts.Wherethese
contactsoccur,thereisavegetationtransitionbetweenthespeciesofQuercus
laceyi,Q.muhlcnhergii,Q.texana,andAcergrandidentatumandthecreekside
seepageshelvesdominatedbyPlatanusocci(ienta[is,Cepiia/anthusoccidentaiis,
Adiantumcapillus-veneris,Thelypteriskunthii,andCladiummariscoides.The
species is normally associated with Aristolochia serpentaria, Carex
edwardsiana,C.planostachys,Linderahenzoin,Senecioohovatus,andVerhesina
virginica.OthercentralTexasendemicsoccurringwithornearP.C6irriiinclude
Chaetopappaeffusa,Clematistexensis,Mateleaedwardsensis,Philadclphus
texensis, Tragianigricans,Tridenshuckleyanus,andStyraxplatanijoliusvar
stcUatus.
Etymology—ThespeciesisnamedinhonorofWilliamF.CarrofTheNa-
tureConservancyofTexas.Billisdeeplycommittedtopreservingthebotani-
,
190 BRIT.ORG/SIDA21(1)
calheritageofTexasandiscurrentlyoneoithemostactiveplantcollectorsin
thestate.
ACKNOWLEDGMENTS
Wewishtothankthecuratorsoftheherbariacitedforaccesstothespecimens
usedinthisstudy.SpecialrecognitionisgiventoGeraldineWatsonv^hoac-
companiedtheseniorauthortothesiteswhereshehadpreviouslycollected
Prenanthes.AmberSwanson,CuratorialAssistantoftheHarvardUniversity
Herbaria,providedadigitalphotographofthedesignated lectotypeof
Prenanthesharhata.WethankGuyL.NesomforhisLatintranslationandfor
reviewingthemanuscript.Appreciationisalsoexpressedtothelandowners
whograciouslypermittedaccesstotheirpropertiesandtoBil1Carrforhisfield
assistanceandaccesstoLoveCreekPreserve.Wealsogivespecialthanksto
DavidRiskindatTexasParksandWildlifeDepartmentwhograntedusaccess
toLostMaplesStateNaturalAreaandreviewedthepreliminarymanuscript.
WealsowanttothankLarryBrownofSpringBranchScienceCenterHerbarium
andSandiElsikandWarrensPruessofRiceHerbariumfortheirassistancewith
specimenrecords.WealsoextendourdeepestgratitudetoLinnyHeagyHer
amazingartistryexemplifiesthedetailsofthenewly-describedPrenanthes
carrii.
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