Notes on the genus Amorphophallus (Araceae) — 5. Amorphophallus konkanensis, a new species from India, and taxonomic reflections on Amorphophallus section Rhaphiophallus

6 Pages·1994·1 MB·English

by  Hetterscheid, W L A

BLUMEA 39 (1994) 289-294
Notes on the genus Amorphophallus(Araceae)— 5.
Amorphophalluskonkanensis, a new species from India,
and taxonomic reflections on
Amorphophallussection Rhaphiophallus
W.L.A. Hetterscheid S.R.Yadav & K.S. Patil
Summary
Anewspecies ofAmorphophallussect.Rhaphiophallus(Schott)Engl.from SWIndiais described.
Themonophylyofandcharacterevolution in sect.Rhaphiophallusis discussed.
DESCRIPTION
Amorphophallus konkanensis Hett., Yadav & Patil, spec. nov. —Fig. 1
Ab A.mysorensis Barnes etFischer in floribus neutrissemicomplanatis, placentationebasali,et ab
A. sylvatico (Roxb.)Kunth in dimensionibus maioribus,spathafusca,placentationebasali differt.
—Typus:K.S. Patil4687-A (CAL nolo),India, Maneri,SindhudurgDistrict, 15-v-1992. Para-
types: K.S.Patil4687-B(BLAT),4687-C(L),both samedataas holotype.
Tuberousherb. Tuber globose or depressed globose, 3-8cm in diam., 3-4.5 cm
high,producing short, rhizomatousoffsets.Lea/solitary; petiole smooth, 29-88cm
long, 0.6-1.5 cm in diam., brown or greenish brown, mottledpinkish and with
whitish stripes; lamina40-96cm in diam.,rhachises winged, except forthemost
proximal parts; leaflets lanceolate,acuminate,4-19cmlong, 1-4cm indiam.Inflo-
rescence long-peduncled; peduncle as petiole, 25-55cm long,0.3-1 cm in diam.;
spatheerect, ovate,acute,notconstricted, limbpoorlydifferentiatedfrombase, 3.3-
8.5 cm long,2.3-7cm in diam.,outsidedirtypinkish withabrownishhue andfaint
brownishspots, veinsdarkpurplish brown, insidemaroon,basewithindarkmaroon,
longitudinally ridged. Spadix stipitate, up to twice as long as spathe, 9.5-16 cm
long; stipe c.0.5 cm long, green;female zone cylindric, 0.8-1.7 cm long, flowers
congested; malezone cylindric, 1.8-3.1 cm long, flowersslightly distant; stamino-
dialzone between femaleand male zone 0.6-1.5cm long, staminodescongested;
U The firstthree papers in thisserieswerepublishedin,respectively, Blumea 36 (1991)467-475
and 39,thepresentissue,pages 237-281 and 283-287;No. 4(byC.I.Peng) willbe publish-
edin Bot.Bull. Acad. Sinica, 1995.
2) Chrysantenstraat28, 1214BM Hilversum,TheNetherlands.
3) DepartmentofBotany,GoaUniversity,TaleigaoPlateau,P.O.Bambolim Complex,Goa404 203,
India.
4) DepartmentofBotany,Shivaji University,Kolhapur416004,Maharashtra State,India.
290 BLUMEA Vol. 39, No. 1/2, 1994
Fig. 1.—a, b: Amorphophalluskonkanensis Hett., Yadav & Patil; a: inflorescence,c. x0.7;
b: lower halfofspadix, c.x 1.7.
appendix elongate conic,apex blunt, 5.5-13cm long,0.5-1cm indiam., dirtyolive
green.Ovaries depressed-globose, diamond-shaped incross section, 2-3 mm in
diam.,0.8-1 mm high,pale green,nearthetop becoming purplish, 3- or4-locular,
one basalovule perlocule; style short, cylindric orconic, 0.2-0.5 mm long, 1 mm
in diam.(base), purplish; stigma large, subcircularor slightly irregular incross sec-
tion,2mm in diam.,0.7-1 mmhigh, verruculate, paleyellow, 3-or 4-lobed,lobes
very shallowly conical or rounded, obtuse, separated by shallow grooves. Male
flowers consisting of4-6 stamens;stamens 1mm long;filaments0.2-0.3mmlong,
entirely connate; antherstruncate, 0.7-0.8mm long, 1-1.5 mm in diam., irregular
in cross section, thecae whitish, connectivebrownish, poresapical, elongate, reni-
form or straight. Pollenpsilate. Staminodes ovate or rhomboidin cross section,
W.L.A. Hetterscheid, S.R. Yadav & K.S. Patil: Notes onAmorphophallus-5 291
slightly convex, 3-6x 2.5-4mm, 1-3 mm high, whitishor with afaintpurplish
hue. Berries pink at maturity, 2-4-seeded; seeds subglobose, 0.3-0.5 cm long,
0.2-0.35cm in diam.2n= 26.
Etymology - Thespecies epithet referstotheKonkanregion inthe south-western
partof MaharashtraState, wherethisspecies is found.
Distribution India,SW MaharashtraState(Konkan region).
-
Habitat&Ecology - Commonthroughout theKonkanforestonlateritesoils, near
bushes. Fl. April-May; fr. May-June.
NOTES ON MONOPHYLY AND CHARACTER EVOLUTION
Amorphophallus konkanensis is clearly amemberofAmorphophallus sect. Rhaphio-
phallus (Schott) Engl. (Engler, 1911) (emend. Sivadasan, 1989), possessing the
characteristic spathe-shape and staminodes. The general morphology and colour-
pattern ofA. konkanensis are very similartoA. mysorensis Barnes& Fischer from
the state of Mysore (India), fromwhich it differs markedly in the semi-flattened
staminodes(vs. globose inA. mysorensis)and the basal placentation (vs. axillary
halfway up thelength ofthe locule inA. mysorensis). Threeother species ofsect.
Rhaphiophallus possess similarly flattenedstaminodesas inA. konkanensis, viz. A.
bonaccordensisSivad. & Mohanan,A. hohenackeri(Schott) Engl, and,A. sylvaticus
(Roxb.) Kunth, allfromsouthernIndia.Ofthese, A. sylvaticus hasanaxile placen-
tationas inA. mysorensis and muchsmallerdimensions,whereasA. bonaccorden-
sisand.A.hohenackeridifferinhaving muchbroaderleaflets, very long, thin stolons
andthespadix equal toor shorterthanthespathe.
SectionRhaphiophallus, ashereunderstood, contains eight species whichare sepa-
rated as a groupby Sivadasan(1989) withinAmorphophallus onthe basis ofthe
large, flattenedor globose neuter organsbetweenthemaleand femalezones. How-
ever, contrary to Sivadasan's statement thatonly species ofsect.Rhaphiophallus
possesses such neuter organs, thereare threemore published species with similar
structures not belonging to this section, viz. A. krausei Engl. [syn. A. sutepensis
Gagnep., A. ximengensis H. Li, from northernBurma, northern Thailand,China
(Yunnan)], A. saraburiensis Gagnep. (central Thailand) andA. albus P.Y. Liu &
.
J.F.Chen(China, Szechuan). Anadditional two new species (A. atroviridis Hett.,
ThailandandA. salmoneusHett. [Philippines (Palawan)], published inthe present
issue, also sharethis character. As a consequence,this charactercannot be useda
priori to distinguish sect. Rhaphiophallus from theremainderofAmorphophallus,
without considering the distributionofthis and othercharacters ofthe sectionin
otherspecies of thegenus(see Table 1on thenext page).
Theaxileposition halfway upthelength oftheplacenta oftheovulesinthreespecies
ofsect.Rhaphiophallus is unique inthegenusbutthis doesnot suffice tosupportthe
monophyly oftheentiresection. Thesameholds forthe globose staminodes,which
arealso only foundinthreespecies of thesection.Thereremainsthestipitate spadix,
a fairlyrare characterinthegenus. Itis alsofoundinanumberofHimalayan-Indo-
chinese species, e.g.A. yunnanensis Engl. (syn. A. kerrii Gagnep.) from Thailand,
292 BLUMEA Vol. 39,No. 1/2, 1994
Table 1.CharacterdistributioninAmorphophallus sect.Rhaphiophallus compared to
A. ‘groupyunnanensis’ andA. ‘group krausei’.
\\ cchhaarraacctteerrss:: 11 22 33 44 55
ssppeecciieess \
AA..bboonnaaccccoorrddeennssiiss SSiivvaadd..&& MMoohhaannaann aa aa aa aa bb
AA.. hhoohheennaacckkeerrii((SScchhootttt)) EEnnggll.. aa aa aa aa bb
AA..kkoonnkkaanneennssiiss HHeetttt..,, YYaaddaavv&& PPaattiill aa aa aa aa bb
AA.. lbonnggiiccoonnnneeccttiivvuuss BBooggnneerr bb ?? ?? ?? bb
AA.. mmaarrggaarriittiiffeerr((RRooxxbb..)) KKuunntthh bb bb aa aa bb
AA.. mmyyssoorreennssiiss BBaarrnneess && FFiisscchheerr aa bb bb aa bb
AA..nniiccoollssoonniiaannuussSSiivvaadd.. aa bb bb aa bb
AA.. ssyyllvvaattiiccuuss ((RRooxxbb..)) KKuunntthh aa aa bb aa bb
AA.. ''ggrroouupp yyuunnnnaanneennssiiss’' aa -- bb bb bb
AA.. ''ggrroouupp kkrraauusseeVi’ aa aa aa aa aa
CChhaarraacctteerrss:: llaa:: aappppeennddiixx pprreesseenntt 44aa:: nneeuutteerroorrggaannsspprreesseenntt
bb:: aappppeennddiixx aabbsseennttoorr ssttuubb bb:: nneeuutteerroorrggaannssaabbsseenntt
22aa:: nneeuutteerroorrggaannssffllaatttteenneedd 55aa:: ssppaaddiixxsseessssiillee
bb:: nneeuutteerroorrggaannssgglloobboossee bb:: ssppaaddiixx ssttiippiittaattee
33aa:: ppllaacceennttaattiioonn bbaassaall
bb:: ppllaacceennttaattiioonnaaxxiilleeeettcc.. ((sseeee tteexxtt))
Laos, China(Yunnan) and N Vietnam, A. corrugatusN.E.Brown from northern
Burmaandnorthern Thailand, A. kachinensisEngl. & Gehrm. (syn.A. bannaensis
H. Li) from north-eastIndia, northernBurma, northernThailand, China(Yunnan)
andLaos.Ifthis characteris anapomorphy, linking thesespecies to sect.Rhaphio-
phallus, thespecies of thelattersectionwouldstillcome out as a monophyletic group
on thebasis ofthestaminodes. Allotherspecies withstaminodeshavesessile spa-
dices, so,even inthatframe, sect.Rhaphiophallus wouldprobably stillseparateas
a monophyletic group.Thespathe-shape ofalleight species is alsoquiterare inthe
genusand occurs only in species whichshow nootherrelevantsimilarities to spe-
ciesofsect.Rhaphiophallus andare thereforeconsiderednotto belong toit (e.g.A.
elliottiiN.E. Brown,.A. interruptus Engl. & Gehrm.). On the basisofthese specu-
lations and awaiting a phylogenetic analysis oftheentire genus(Hetterscheid, in
prep.), itseems fairto considersect.Rhaphiophallus monophyletic. Thisprovides
theopportunity to discuss comparatively some charactersofitsspecies. Theposition
ofA. longiconnectivus Bogner (ined.) insect.Rhaphiophallus is uncertainatthemo-
mentbecause ofdifficultiesininterpreting some charactersoftheonly knownspeci-
men. Evenitsstatus asspecies in relationtoitsnearest morphological allyA.marga-
ritifer (Roxb.) Kunthis under discussion. Apreliminary cladisticanalysisofsect.
Rhaphiophallus using allpossible alternativestatesofsome charactersofA.longi-
connectivus andentering itas a separatespecies, indicate itis thesister species of
A. margaritifer.
W.L.A. Hetterscheid, S.R. Yadav & K.S. Patil: Notes on Amorphophallus-5 293
A geographic trendhas beensuggested (pers. comm. J. Bogner, Munich, Germany)
inthissection ofareductionoftheappendix inspecies going from Southto North
Indiabutthis trendis brokenby theoccurrence ofA. konkanensisnorth ofthedis-
tributionofA. mysorensis. This latterspecies shows a marked variationin the ap-
pendix-length whichhasbeeninterpreted as beingintermediatebetweenthesituation
in, on theone hand,A. sylvaticus andA. nicolsonianusSivad. (respectively S and
SWIndia) possessing along appendix and, onthe otherhand, A. margaritiferand
A.longiconnectivus (northern India) bothlacking an appendix or the appendix being
reducedto amerestub. Thischaracter ofbothA. margaritiferandA. longiconnec-
tivusmustbeconsideredaderivedcharacterwithintheframeworkofsect. Rhaphio-
phallus, sinceitoccurs in speciesofamonophyletic 'subunit'ofsect. Rhaphiophal-
lusmadeupofallspecies withglobose staminodes(a uniquecharacterinAraceae!).
Thelackofanakedappendix maybetheresultoftwo alternative evolutionary path-
ways, onebeing thedifferentiationoffertilemaleflowersontheappendix, theother
being anactualsuppression oftheappendix. Twocluespoint to thelatteralternative.
First, A. mysorensis shows markedvariationin appendix-length, whereby the ap-
pendix maybe 'reduced' to amere shortstub. Atleast one specimen isknown of
A. margaritifer, showing a similarstub. Second,in allspecies of thegroupwith
globose staminodes which possess anappendix themalezonereaches to thetop of
the spathe. InbothA. margaritiferandA. longiconnectivus this situationis similar.
If, on a non-suppressed appendix male flowers would have differentiated, this
wouldhaveresulted ina verylong malezone reaching farbeyond thespathe, as for
the 'malezone +appendix' of theotherspecies. Thereforeit is concludedthatthe
lack ofa nakedappendix in bothspecies discussed resulted from asuppression of
the entireappendix. Theotherexplanation (male flowersdifferentiatedon the ap-
pendix) is considered by Hetterscheid (in prep.) to be the cause ofthe lack ofa
smoothappendix inA. coudercii(Bogner) Bogner (Laos & Vietnam) andmayalso
explain thestaminodialappendix in.A. napalensis (Wall.)Bogner & Mayo (Bhutan,
Nepal, NIndia) andA. sumawongii (Bogner) Bogner & Mayo (Thailand).
Theinterpretation ofthesterilestructuresbetweenmaleandfemalezones as stami-
nodesisbased onobservationsofserial homology betweenthemaleflowers andthe
sterilestructures. Thedevelopment ofthis typeofstaminodemayhaveoccurred more
thanonce inAmorphophallus. They arealso foundina groupofmainly Himalayan-
Indochinesespecies (seeabove) and inA. atroviridis Hett., amemberofa groupof
long-tubered species (see the description inthepresentissue,page245). The phylo-
genetic interrelationships ofthesegroupsare unclearatthemoment,so anyspecula-
tionontheamount ofhomoplasy intheoccurrence ofthesestaminodesin thegenus
is futile.However, morphological investigation by the first authorinto allspecies
possessing such staminodesindicatesthatthey are derivedin asimilarmannerfrom
themaleflowers (assuming thatinall thesecases the presence ofstaminodesis a
derivedcharacter). In anumberofthese species thefilamentsofat leastthe lower
maleflowers are entirely connate andtheresulting column('cushion' in Sivadasan
etal., 1994) is often enlarged in the lowermostflowers. Flowers morphologically
intermediatebetweenthelatterandthestaminodesareoftenfoundandthey indicate
thatthetransitionisbrought aboutby areductionofthethecae,leaving only thecol-
294 BLUMEA Vol. 39, No. 1/2, 1994
umnandtheconnective-tissue as theactualstaminode.Inthegroupoflong-tubered
species this same derivationcan bebased by invoking topographic homology. Inall
species ofthis groupthecolumnin thelowermostmaleflowers is extremely large,
reducing theantherstomerestubson topofitandoftenpushing themapart, thereby
resembling thestaminodialcondition.Thetransition to staminodesinthis groupis
then 'completed' inoneofitsspecies, viz.A. atroviridis.
Variationinthesculpture ofthepollen wallinsect.Rhaphiophallus is remarkablebe-
ing psilate (A. konkanensis, A. margaritiferandA. mysorensis), finely verrucate (A.
sylvaticus) orstriate(A. nicolsonianus). Palynological investigations (VanderHam
& Hetterscheid, inprep.) show thatthis variationis muchwider thanin othermono-
phyletic species groupsinAmorphophallus.
ACKNOWLEDGEMENTS
Thanks are duetoDr. Jin Murata(BotanicGarden, UniversityofTokyo) and V.T.Chougule(prin-
cipal ofSmt.K.W. College, Sangli)forencouragement,to Dr. S.M. Patil (head,Departmentof
Botany, Shivaji University) forprovidingnecessary facilities, Dr. M. Sivadasan (Department of
Botany, Calicut University) for valuable comments, Dr. A.Hay (Sydney) andMr. P.C. Boyce
(Kew)for correctingthe manuscript,Dr. J.F. Veldkamp (L)forproviding theLatin diagnosis, and
Dr. R.W.J.M.van derHam (L)forprovidingthepollendata.
REFERENCES
Engler,A.1911.Araceae-Lasioideae. In:A.Engler(ed.),Das Pflanzenreich IV.23C,Heft48.Leip-
zig.
Sivadasan,M. 1989.Amorphophallusnicolsonianus (Araceae),anewspeciesfrom India,andanote
onA. sect. Synantherias.Willdenowia 18: 435-440.
Sivadasan,M.,N. Mohanan &G.Rajkumar. 1994.Amorphophallusbonaccordensis,anewspecies
ofAraceae fromIndia. Blumea 39: 295-299 (thisissue).