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BLUMEA 45 (2000) 399-402 Begonia siccacaudata (Begoniaceae). A new species from Sulawesi J. Doorenbos Laboratory forPlant Taxonomy,WageningenUniversity, P.O..Box 8010, 6700 EDWageningen,The Netherlands Summary AnewspeciesBegoniasiccacaudata isdescribed.Itbelongstothe sect.Petermannia but isdistin- guishedfrom otherspeciesby beingstemlesswith ashort fleshyrhizome. Thefemale flowers are solitary, the male flowers areborne ona many-floweredthyrsoidinflorescence ofatypenot yet described within thegenus.Theepithetsiccacaudata referstotheaxesofthe inflorescences which persist foralongtime afterdyingoff. Key words: Begoniasection Petermannia,Malesia,Sulawesi. Introduction During atouristictripthroughIndonesiain 1993J.J.Wieringacollectedmaterialofa Begonia on Sulawesithatcouldnot beidentified.Ithadthehabitofaspecies ofsect. Diploclinium butoncloserinspection wasfoundtobelong tosect.Petermannia.The lattersectioncomprises about200species (Doorenbosetal., 1998),although someof thesemaybesynonymous,whileontheotherhandothersundoubtedly stillawaitdis- covery. As thereexists no criticalreviewofthissectionandmanyspecies areknown only from one,often incomplete description, itmight seem inappropriate topresent yetanotherspecies. However,thefact thattheplant shows onecharacterthatisprobably newto sect.Petermanniaandanotherthat may be newtothewhole genusBegonia clearly warrants itsdescription as anewspecies. TAXONOMIC NOTES Of the21 species ofBegonia that have beendescribedfrom Sulawesi, 17belong to sect. Petermanniaand4to sect.Sphenanthera. Notably absent are species ofsect. Diploclinium, asection wellrepresented inBorneoandparticularly inthePhilippines (Doorenboset al., 1998). Initially itseemedas ifB. siccacaudatafilledthis gapbut thesolitary, protogynous femaleflowersandthethyrsoid maleinflorescenceplace it firmlyinPetermannia.Species ofthelatter section characteristically are subshrubs withupright stems25-200cm high,although somehave creeping stems, rooting at thenodes, ascendant or with upright laterals, anda few are lianescent.A stemless species ofsect.Petermanniawithashortrhizomehasnot yetbeen described, unless B.holosericea Teijsm. & Binn. fromTernateor B.promethea Ridl.fromBorneocan besoregarded. Forthepresent, however,thedescriptionsofthesetwo species are too 400 BLUMEA Vol. 45, No. 2, 2000 vagueto be certainoftheirprecise habit.Photosofthetype materialreproduced by Smithetal.(1986) areinadequate to resolve this question. Furthermore, theinclusionof these two species in sect. Petermanniaremains in doubt.Begonia siccacaudata also differs from other species in this section in the formofthemaleinflorescence, althoughitscomposition followsthepatterncharacter- isticforsect.Petermanniaas describedby Irmscher(1914). ClosesttoB.siccacaudata inthisrespect is B. naumoniensisIrmsch., butin thatspecies the nodesofthemain axis bear2-4 peduncles insteadofasingle one, andno stipules. Moreover, thefirst lateralaxes ofthedichasiumarenot reducedandhavebracts, whicharenot foundin B. siccacaudata. Oi5tside the sect. Petermanniaspecies in which femaleand male flowersareborneindifferentparts oftheplant arerare. Twoexamples cometo mind. The Brazilian section Trachelocarpus comprises stemless plants with the female flowerssolitary ontherhizomeandthemaleflowersinumbellatecymeswithstrongly reducedaxes. Begonia longipetiolata GilgoftheAfricansectionTetraphila is similar intheserespects. Inbothcases,however,thepeduncles ofthemalecymes areimplanted ontherhizome, not onaseparate axis. In 1898S.H.KoorderscollectedaBegonia inSulawesiofwhichhehadadrawing made that was later includedin a posthumous publication (Koorders, 1922). This drawing appearsto depictleaves, maleandfemaleinflorescencesall arising froma short rhizome. The caption reads "Begonia spec,nova (?) (affinis Strachwitzia (?) Warburg)". Begonia strachwitzii, atthatmoment anomen nudum,was validatedby Irmscher(1913)fromWarburg'smaterial, presumably thesamespecimen thatKoorders saw. That he collecteda similar plant is evidentfrom thepicture of thefruits.The habit,however, shows a very differentspecies. Inmy opinion, two plants havebeen mixedup,presumably atBogor,so thatonecannot be surethatbothwere collectedin Sulawesi. It remainspossible thatinadditionto B.siccacaudata thereexists another stemless Begonia ofsect. Petermannia,perhaps even inSulawesi. DESCRIPTION Begonia siccacaudata J.Door., spec. nov. —Fig. 1 Herba parva, acaulis, rhizomate brevi crasso, species unica in sectione habitu tali. Inflorescentia masculaterminalis, thyrsoidea,folia vulgoabsentia,stipulaepraesentes etpersistentes,pedunculosmonochasia umbelliformes gerens,axibuslateralibus reductis, bracteis absentibus. Flos femineus solitarius in axis foliolorum rhizomati insidens. — Typus: J.J.Wieringa 1902 (holoWAG),Indonesia,Sulawesi Selatan,c. 12kmESE of MarosnearBantimurungWaterfalls,5°02' S, 119° 41'E,60 m a.s.l.Paratypus: J. van Veldhuizen.v.n.(WAG). Stemless monoeciousperennial herb. Rhizome tuberous, branched,branches up to 3 cm long and 1.1 cmthick, greenatfirst, laterlightgreyish brown,smoothbut fora fewremnants ofstipules andpetioles. Leaves glabrous. Stipules narrowly triangular or slightly ovate,rapidly shrivelling but notcaducous, upto5 mmlong and2-3mm broadatthebase, acutewithahairupto2mmlongimplantedadaxially justunderthe tip.Petiolesupto5 cmlong, upto2 mmthickwhenfresh,muchthinnerwhendried. Leafbladebroadly ovate,usually asymmetrical, slightly fleshy whenfresh but very thinand brittlewhen dried, upperside darkgreyish greenwithrows ofwhite spots J.Doorenbos: Begoniasiccacaudata, anew speciesfrom Sulawesi 401 Fig. 1.Begoniasiccacaudata J.Door. a.Habit,showingthe distinctive dry,persistent peduncles; later, the main axis ofthe male inflorescence will dryoutin a similarway; b.male flower; c.an- droecium; d.stamen; e.female tepal;f. styles; g.fruit.—Drawn afteraliving topotype. alongtheedge andbetweenthenerves, darkor lightredbeneath, upto5-6by5 cm, slightly cordate, acute, edge entire or serrulate, fimbriatewith minutehairs up to 1 mmlong. Maleinflorescence a glabrous thyrse. Mainaxismoreor less geniculate, internodesto35mmlong, ateachinternode2stipules, like thoseon therhizomebut withoutor withonly aminutehair,leavesnearly alwaysabsent,occasionally rudimen- tary, peduncles in theaxilsofthe (absent) leaves, up to 45mm long, bearing cymes 402 BLUMEA Vol. 45, No. 2, 2000 terminatedbyapedicelled maleflowerflankedby two monochasiawithalmostcom- pletely reduced axes. Maleflowersonpedicels 20-28mm long, tepals 2, elliptic or oval,obtuse,9-10by 11-12mm,entire, brightrose-pink.Androeciumactinomorphic, stamina20-40,filamentsunequal, thelongestonesinthecentre,0.5-1.5by thelength oftheanthers,connectivenotvisiblebetweenthepollensacsandnotproduced. Pedicel, tepals andandroeciumare shedasawhole,thepeduncle driesoutbutremainson the plant; eventually themainaxisoftheinflorescenceincluding the stipules also dries outandpersists ontheplant,atleastforsometime(hencethespecific epithet).Female inflorescences solitary ontherhizome, glabrous, peduncle (ifpresent,itiscoveredby stipules and extremely short) apparently bearing one flower; pedicel initially short butelongating to up to 45 mm intheripe fruit, 1 mm thickwhenfresh; bracteoles absent;tepals 5,11-13by7-9mm,oblong tolanceolate,entire, pale pink-rose. Styles 3,shortlyunitedatbase,bifidathalfoftheirlength,thebranches unitedby astigmatic bandthatspiralsoncearoundthem.Ovary with3locules,placentae axillary,bilamellate withovules onbothsurfaces. Fruit erect, glabrous, 8-10mmlong,greatestdistance betweenthedistalendsofthewings 11-12mm,tepals andstyles ± caducous,wings 3,subequal, triangular, widestator nearthetop. Dehiscence offruitnot yetknown. Distribution—Known only fromthetypelocality. Habitat—Forest.Plantsfoundgrowingonaverticalwallattheentranceofacave. Note—ThematerialWieringacollectedconsistsofherbariumspecimens offruiting plants. Afew smallplants werebrought toWageningen alive andplanted ina green- house where in due course they started to flower. Maleflowering was profuse but only 4femaleflowers developed. These were pollinated. It seemedthat some seed- setoccurredbut noseedlings grew. When itbecameclearthattheseefforts toobtain youngplants had failedtheold were inapoorconditionandfailedto produce more femaleflowers.Accordingly, although thefemaleflowershadbeendescribed,all had been usedforpollination andwere not preserved. Thustheparatypeconsists only of maleinflorescences.Failuretoreproduce thisplantwas disappointing asitscompact habitandprofuse brightpinkmaleflowers give it considerableornamentalvalue. ACKNOWLEDGEMENTS Iamindebted toDr.J.J.Wieringaforthedelegationofhis Begoniamaterialtomeforidentification and description, and to staffmembers oftheLaboratoryfor Plant TaxonomyatWageningenfor theirhelpand their criticalcomments onthe manuscriptofthis article. Iam also most gratefulto the editorand toananonymous referee whotook much trouble toimprovethe text. REFERENCES Doorenbos, J., M.S.M. Sosef& J.J.F.E.deWilde. 1998.The sections ofBegonia.Wageningen Agricultural UniversityPapers 98-2. Irmscher,E. 1913.Neue BegonienPapuasiensmitEinschluss vonCelebes. Bot. Jahrb.Syst. 50: 335-385. Irmscher,E. 1914.Die VerteilungderGeschlechter in der Infloreszenzen derBegoniaceenunter Beriicksichtigung der morphologischenVerhaltnisse. Bot. Jahrb.Syst. 50,Suppl.: 556-577. Koorders,S.H. 1922.Supplementop het eersteOverzicht derFlora vanN.O.Celebes II:pi. 97, III:47. Smith,L.B.,D.C. Wasshausen,J. Golding& C.E. Karegeannes. 1986.Begoniaceae.Contr. Bot. 60. Smithsonian Institution Press,WashingtonD.C.