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Nuytsia9(3): 421-425(1994) 421 A newspecies ofNicotiana (Solanaceae) from nearBroome, Western Australia D.E. Symon'andKevinF. Kenneally^ 1 C/-TheBotanicGardensofAdelaideandStateHerbarium,NorthTerrace, Adelaide,SouthAustralia5000 2WesternAustralian Herbarium,DepartmentofConservationandLandManagement, POBox 104,Como,WesternAustralia6152 Abstract Symon, D.E. and Kenneally, Kevin F. A new species of Nicotiana (Solanaceae) from near Broome, Western Australia. Nuytsia 9 (3): 421-425 (1994). Nicotiana heterantha Symon & KenneallyisdescribedfromnearBroome,WesternAustralia. Thenewspeciesisknownfromonly two populations, both of which are under threat from grazing. It appears most closely related to N. rosulatasubsp. rosulata. Introduction AnewspeciesofNicotiana,namelyN. heterantha,aKimberleyendemicisdescribedinorderto validatethenameforuseinaforthcomingbookontheplantsofBroomeandtheDampierPeninsula. TherehavebeenthreeaccountsofNicotianainAustraliainrecenttimes. Apioneeringaccountby Burbidge(1960)broughttogetherrecordsuptothatdateanddescribedfivenewspeciesandtwonew subspecies. ThiswasfollowedbyHorton(1981)whodescribedtwonewsubspeciesand reducedone ofBurbidge'sspecies(N. hesperis)totherankofsubspecies. TheacountofNicotianaintheFloraof Australia,Purdieetal. (1982) wasbasedon Horton. Sincethen Symon (1984)hasdescribedanew species, N. burbidgei from near Dalhousie Springs in the far north-east of South Australia, and Clarkson & Symon (1991)describedN. wuttkeifromnorth-easternQueensland. Taxonomy NicotianaheteranthaSymon &Kenneally, sp. nov. (Figure 1) Herba annua decumbens, pilis simplicibus et glandulosis. Folia radicalia petiolata; laminae ellipticae vel obovatae ad basim attenuatae; apices obtusi. Folia caulina ex axillis caespitosa. Inflorescentiaracemosa,filometallicosimilis;bractisparvis;floresinterdumcleistogamae. Calyx7-9 mmlongus,lobissubaequalibus,apicibus triangularibus. Corollaminutepubescens; tubus2.5 cm 422 NuytsiaVol.9,No.3(1994) Figure1. Nicotianaheterantha A-floweringplant(scalebar=4cm), B-corollaofchasmogamousflower(scalebar=1.75 cm),C-budofcleistogamousflower,D-corollaofcleistogamousflower, (CandDscalebar=4mm),E-capsule(scalebar =4.5mm), F-seeds(scalebar=0.5mm). DrawnfromapotplantgrownfromseedofKenneally 11338. 1 D.E. Symonand K.F. Kenneally, Nicotianaheterantha 423 longus;limbus0.7-1cmlongus;lobilimbiemarginati. Staminaquattorsubdidynamainfauci,quintum brevi filamento semiadnatum. Capsula ellipsoidea 8-10 mm longa. Semina angularia reniformia brunneareticulata. Typus: Buckleys Bore, 11 km N of Broome, Dampier Peninsula, 17° 5rS, 122° 13'E, Western Australia,J.B. Martin 225, 8Mar. 1992 (holo: PERTH2169819;iso: AD,CANB, K). Annualorshort-livedperennialherb,branchingnearthebase. Decumbentstemsdeveloptuftsof leaves atthelowernodes. Leavesatfirstbasal, 2-10x 1-4.5cm,commonlyc. 7x 2.5 cm, petiolate, elliptic to obovate, apex obtuse, base attenuate, margin entire, petiole 2-2.5 cm, narrowly winged, attachmenttostemsimple. Leavesatfirstbasalandeauline,theseintimereplacedbytuftsofleaves at the stem nodes and in the lower parts ofthe inflorescence. Indumentum ofsimple and minute globular-headed glandularhairs, more common on youngparts andcalyces but neverconspicuous, leaves and wiry stems glabrescent. Inflorescence a simple or sparsely branched raceme, the axis relatively slenderandwiry, to 1 m long, decumbent. Stem leaves soon reducedto linear-triangular mm bracts3-5 long, tuftsofleavesdevelopatthe lowernodes (seeabove),from theseaxillarytufts ofleaves short flowering axes 1-5 cm long with 2-5 flowers may develop; pedicel c. 7 mm long. Chasmogamousflowers{Kenneally1 2>2>%):calyx7-9mmlong,thelobesjoinedbymembrane2-3mm, thelobesfreefor2mm, lobeapextriangular,allminutelyglandularpubescentwithinthelowerhalf, limb0.7-1 cm long,dividedabouthalfway, lobeapexemarginate. Fourupperanthersonfilaments 1.5-2mmlong,thelowerfifthantheronfilament6-7mmlong. Anthers 1mmlong;yiy/e2.8cmlong; stigma capitate, exsertedjust beyond the four anthers. Ovary 2 mm, conical, sparsely minutely glandularpubescent,basesurroundedbycircularfleshydisc. Cleistogamousflowers:calyxasabove mm mm butcorollatubeandlobesc. 5 long,notexpanding. Capsulec. 8-10 long,apexacute,equal toorexceedingthecalyx,dividingtofourvalveswhenmature,thecalyxtubeandcapsuleoftenslightly constricted at aboutone-quarter oftheirlength, the lower quarter somewhat thicker and hardened. mm Seedsto1 long,bluntlytriangulartoangularlyreniform,reticulatewithsharp-edgedwavyridges, thecellsdeeply concave,brown. Otherspecimensexamined. WESTERNAUSTRALIA: CoconutWell, 15kmNofBroome, 10May 1985, Foulkes 237 (AD, CANB, K, PERTH); Coconut Well, 15 km N ofBroome, 17 June 1984, K.F. Kenneally9031 (CANB,PERTH);BuckleysPlain, 10kmNofBroome, behindO.T.C. station, 1 Sept. 1992,Kenneally 11338 (PERTH); BuckleysPlain O.T.C. side, 7 kmNofBroome,Dampier Peninsula, 17°54'S, 122°15’E,24April 1992, Martin226(PERTH). Distribution. This istheonlyNicotianasofarcollectedfromnearBroome. Itformslowspreading coloniesinandoutofMelaleucathicketsonseasonallywetblackclayinanareaknownasBuckleys Plain northofBroometoaboutCoconutWell. (Figure2) Floweringperiod. May-June. Thespeciesisfacultativelycleistogamous. Somespecimenscollected inthefieldclearlyhavewelldevelopedandopencorollas,othershavereducedcorollas. Severalplants cultivatedinAdelaideduringthesummers werecleistogamousandsignsofthecorolla werescarcely visible. Thecauseofthesevariationsisnotknown. Affinities. ThenewspeciesappearsmostcloselyrelatedtoNicotianarosulatasubsp.rosulata,thishas more erect, stouterinflorescences which are morebranched above and hence the flowers are more concentratedontheterminalpartsofthe stems. However, there areafew specimensofN. rosulata suhsp.rosulata atADandPERTHwithfloweringaxes equallyslendertothenewspecies. Thenearest 424 NuytsiaVol.9,No. 3(1994) Figure2. Nicotianaheterantha forminglowspreadingcolonie.sonblackclayontheedgeofaMelaleucaacacioides thicketon BuckleysPlainnorthofBroome. collection of N. rosulata to the new species is one from Pardoo about 4(X) km to the southwest. N. heteranthadiffersfromallotherAustralianspeciesexcept N. debneyiinitschromosomenumber (see below). In addition the mostly cleistogamous flowers, tufted growth, and slender wiry stems distinguishitfromallotherAustralianspecies. Notes. Theaxillarytuftsofleavesdevelopingatthelowernodesoftheinflorescencesandtheirshort racemesofflowers areunusualfeaturesdistinguishingthisspecies. Chromosome number. 2n = 48 (from Kenneally 11338). Root tips counted by Dr D.L. Hayman, GeneticsDepartment,UniversityofAdelaide. DrHaymancommentsthat thepresenceofonly one pairofchromosomeswithobvious nucleolarorganisingregionssuggeststhatitisan allopolyploid. ThebasechromosomenumberforthegenusNicotianaisx=12andallAmericanspecieshavethis ormultiplesofit(Goodspeed 1954). TheonlypreviousAustralianspecieswithmultipleofx=12were thetwosubspeciesofN.debneyi n=24,2n=48andhenceatetraploid (Horton 1981). N. debneyi , occurs in eastern Australiaand is theonly Australian species toextendtoNewCaledoniaandLord Howe Island. Although the ecology of N. heterantha is similar to that of N. debneyi subsp. monoschizocarpa, theplantsdifferinmanycharacters. AllotherAustralianspecieshavealongseries ofaneuploid numbersrangingfromN. cavicolan =23 toN. wuttkein= 14. Thisnumber2n=48separatesN.heteranthafromN.rosulata2n=40inadditiontomorphological differences. D.E. Symonand K.F. Kenneally, Nicotianaheterantha 425 Conservationstatus. CALMConservationCodesforWesternAustralianFlora:PriorityOne-Poorly KnownTaxa. This speciesisknownfromonly twopopulations inthesamearea,both ofwhich are underthreatfromgrazing. Etymology. FromtheGreekhetero-differentandanthos-flower,inreferencetothetwodistincttypes offlowersfoundinthisspecies. Acknowledgements TheassistanceofBromeBotanicalSocietymembersBrianCarter,PaulFoulkes,JohnMartinand TimWillinginobtainingmaterialandmakingfieldobservationsofNicotianaheteranthaisgratefully acknowledged. References Burbidge,N.T.(1960). TheAustralianspeciesofNicotiana L. Solanaceae. Austral.J.Bot. 8: 342-378. Clarkson,J.R.&Symon,D.E.(1991). Nicotianawuttkei(Solanaceae),anewspeciesfromnorth-easternQueenslandwithan unusual chromosomenumber. Austrobaileya3: 389-392. Goodspeed,T.H.(1954). ThegenusNicotiana. ChronicaBotanica,Vol. 16. Horton.P(1981). AtaxonomicrevisionofNicotiana(Solanaceae)inAustralia.J. AdelaideBot.Card. 3: 1-56. Purdie,R.W.,Symon,D.E. &Haegi,L.(1982). Solanaceae. FI.Austral.29:38-57. Symon,D.E.(1984).AnewspeciesofNicotiana(Solanaceae)fromDalhousieSprings,SouthAustralia, J.AdelaideBot.Card. 7; 117-121.