The occurrence and taxonomic relationships of Burmannia wallichii (Burmanniaceae) in Malesia

5 Pages·1996·0.46 MB·English

by  Saunders, Richard M K

BLUMEA 41 (1996) 333-337
The occurrence and taxonomic relationshipsof
Burmanniawallichii (Burmanniaceae) in Malesia
Richard+M.K. Saunders
DepartmentofEcology& Biodiversity,The University ofHongKong,
PokfulamRoad,HongKong
Summary
Burmannia wallichii (Miers)Hook.f.(Burmanniaceae)is shown tooccurin Malesia. The similari-
ties between this species and related saprophyticBurmannia species from Southeast Asiaare dis-
cussed, and theFlora Malesiana key publishedby Jonker (1948)is amended accordingly. A new
taxonomic descriptionofthe speciesisprovided.
Introduction
Thefamily Burmanniaceaesensu lato(inclusiveofthesegregatefamily Thismiaceae)
consistsof 13generaand c. 130species ofsmallherbaceous saprophytes and auto-
trophs. Thegeographical distributionofthefamily isessentially pantropical, although
alsoextending into sometemperateregions. Theautotrophic species generallyoccur
as sparse individualsin open fields andsavannahs, whereas thesaprophytes occur
almostexclusively on decaying leaves, wood and roots in the deep shade ofwet
tropical forests.Thesaprophytes can easily beoverlooked by collectors, sincethey
possess underground tubersthatonly produceaerial partswhen flowering orfruiting;
as a consequencecomparatively few specimens areavailableforstudy in herbaria.
Themostrecent comprehensive taxonomicrevision ofthefamily Burmanniaceae
is the monograph by Jonker (1938), although laterregional revisions ofSoutheast
Asiantaxa havebeenpublished (Jonker, 1948;Backer&Bakhuizenvan denBrinkf„
1968:213-215; Saunders,inpress).
Ridley(1907,1924) believedthatthespecies Burmanniawallichii(Miers) Hook.f.
was indigenous totheMalayPeninsula, citing fourofhisown collectionsfromSinga-
pore, Pahang, Selangor andKedah intheformer publication. Probably as a conse-
quenceofthesereports, Jonker(1938) includedtheMalayPeninsulawithinthedistri-
butionalrangeofthespecies, despite thefactthathehadnot examinedany Malesian
collectionsofthespecies duringthe preparation ofhis monograph. Itwas presum-
ably thelack of unequivocal B. wallichiispecimens from theMalay Peninsulathat
subsequently ledJonker(1948) toomitthespecies entirely fromhisFloraMalesiana
account. During thepreparation oftheaccount oftheBurmanniaceaefortheAngio-
spermFloraofSingapore (Saunders, inpress), however,a Singaporean specimen
was identifiedas B. wallichii;the occurrence and taxonomicrelationships ofthis
species in Malesiaarethereforediscussed.
334 BLUMEA Vol. 41, No. 2, 1996
other- 22
measurements oobbttuussee hhaallff--eelllilpip--mmmm))
aabbsseenntt;;
where
ccmm mmiinnuuttee 00..55 pprreesseenntt
mmmm bblluuiisshh wwiitthh ttoo xx
on except 44..55 ccrreessttss
based wwaalllliicchhiiii 44..55--66..55--1111 11--22--22..88 oorr TTrriiaanngguullaarr OOrrbbiiccuullaattee,, HHaallff--lliinneeaarr ((cc.. ssppuurr
1948) l(l(--33)) WWhhiittee aappeexx ttiiccaall AAppiiccaallbbaassaall
BB..
wallichii
(1938, mmmm
hhaallff--
Bfo.r Jonker oovvaattee aappeexx ttoo 4242xx ccrreesstt;;pprreesseenntt
ttoo cc..
aappiiccaall
Datafrom ttrriiddeennttaattaa cm mmmm TTrriiaanngguulalarroobbttuussee HHaallff--eelllliippttiiccaalloorrbbiiccuullaattee,, ssppuurr
6-14cm
species. 6-14 11..55--22 11--33 wwiitthh AAbbsseenntt SSiinngglleebbaassaall
abstracted BB.. ?7
related yyeellllooww
ssuubb--
species
closely wwiitthh wwiitthh mmiinnuuttee ttoo hhaalfl-f-qquuaaddrraanngguulalarr,, mmmm ccrreessttss;;pprreesseenntt
four other sstteeeenniissiiii cm mmmm wwhhiittee TTrriiaanngguullaarraappeexx OOrrbbiiccuullaattee,, HHaallff--eelllliippttiiccaall 11xx..55 aappiiccaall ssppuurr
and dfoatra BB.. 22-6-c6m 00..55--11..55 2211oorr PPuurree lilmimbb oobbttuussee 44cc..55.. TTwwoobbaassaall
wallichiipossible; wwiitthh ttwwoo lloobbeess trutrnucnactaet,e,
mmmm aabbsseenntt;;
wwiitthh
ssoommeettiimmeess nnaarrrrooww,,llaatteerraall 33--44 aabbsseenntt
Burmannia where oobblloonnggaa ccmm mmmm lilmimbb OObbttuussee--bbiiffiidd,,iinnvvoolluuttee,, ttrriiaanngguullaarr HHaallff--oobboovvaattee,,55-xx7-7.5.5 ccrreessttss ssppuurr
of collection 77--1155 11..55 l22oorr WWhhiittee,,yyeellloloww AAbbsseenntt AAppiiccaallbbaassaall
BB.. cc.. 1 cc..
characteristics per aaccuummii-- hhaallff-- mmmm
wwiitthh aappeexx 1, 22
counts ttoo xx ccrreessttss;;aabbsseenntt
wwhhiittee wwiitthhaappiiccuullaattee Lanceolate-ovate', 44
10 mmaallaassiiccaa cm mmmm oorrlilmimbb Lanceolate-ovate mmmm HHaallff--oorrbbiiccuullaattee cc.. aappiiccaall ssppuurr observ.).
morphologicalusing 55..55-8-c8m 11..55--22 2(l(oor)r2) PPuurrpplleeyyeellllooww TTrriiaanngguulalarrnttnaooatete 00..55 eelllliippttiiccaall,, TTwwoobbaassaall (pers.
BB.. I cc..
collections,
orbiculate
of
aanntthheessiiss:: (1938).
Comparison lloobbeess:: lloobbeess::
fflloowweerrss
herbarium ssttrruuccttuurree::
aatt iinnfflloorreesscceennccee:: ccoolloouurr:: wwiinnggss:: OccasionallyJonker
ppeerriiaanntthh ppeerriiaanntthh
stated. hheeiigghhtt length: ooff
Leaflength:
1.four NNuummbbeerr PPeerriiaanntthh PPeerriiaanntthh SSttaammeenn Fide
Tableof wise PPllaanntt Leaf ppeerr OOuutteerr IInnnneerr 1)2)
R.M.K.Saunders: Burmannia wallichii in Malesia 335
TAXONOMIC RELATIONSHIPS
Burmanniawallichiipossesses closetaxonomicaffinities with four otherspecies
within theMalesianphytogeographical region, viz. B. malasicaJonker,B. oblonga
Ridl B. steenisii Jonkerand B.tridentataBecc. (Table 1). All five species are
small achlorophyllous saprophytes, lacking thebasalrosette ofleavestypical ofthe
autotrophic species ofthegenus;theleavesarereducedtosmallbract-likestructures
thatare appressed to thestem.Similaritiesalsoexist intheformationofonly 1 or2
flowersperinflorescence(rarely 3inB. tridentata).
Themostimportant diagnostic featuresfordistinguishing betweenthese taxa are
charactersoftheperianthandandroecium(Table 1).Although theouter perianth seg-
mentsofall fivespecies aresomewhatenlarged andcarnose atthemargin,consider-
ablevariationexists inthesizeandshapeoftheinnerperianthsegments:according to
Jonker(1938, 1948),they are largest in B. malasica (lanceolate, to c. 0.5mmlong),
highly reduced in B. steenisiiandB. wallichii, and entirely absentin B. oblonga
andB. tridentata.Burmanniamalasicaappearstoshow considerablevariationinthis
character, however,and thedistinctionbetweenthis species andits close relativeB.
lutescensBecc. is consequently not as absoluteas suggested by Jonker(ll.cc.).The
threeperianth wings attachedtotheoutsideoftheperianth tube arealso diagnostical-
lyimportant: they are typically upto 4mmindiameterinB.oblonga, up to c. 2mm
in diameterinB. malasica, B.steenisiiandB. tridentata, butreducedto onlyc. 0.5
mmdiameterin B. wallichii.
Although thestamens are fusedto theinnerwall oftheperianth tubeandare re-
ducedtojustapairofthecaeseparated by aconnective,thestructure ofthis connec-
tiveis highly variablewithinthegenusandtaxonomically valuable.Many species of
Burmanniapossess connectives with two positioned papillose apical
crests,and asingle pendent basal spur.Burmanniasteenisiiis typical ofthis form,
but theother fourspecies all differby lacking either theapical crests (B. oblonga
and B. wallichii) and/orthebasal spur (B. malasicaand B. oblonga), orelse by
possessing asingle, centrally positioned apical crest(B. tridentata).
Thekey toMalesianspecies provided by Jonker(1948: 15) canbeamendedtoin-
cludeB. wallichiiby replacing couplets 11-14with thefollowing:
11. Inner perianthlobes absent.
12. Perianth lobes simple.Connective with anapical,papillosecrest and abasal,hanging,obtuse
spur B. tridentata
12. Perianth lobesbifid. Connective withoutcrest andspur B. oblonga
11. Innerperianthlobespresent, sometimes very small.
13. Connectives lackingbasal spur.
14. Plantfloweringup to 8 cm height; 1 (or2) flowers per inflorescence; flowers subsessile
B.malasica
14. Plantfloweringup to 23 cmheight; upto 11 flowers per inflorescence;flowers pedicellate
B. lutescens
13. Connectives with basal spur.
15. Plantfloweringup to6cmheight;connectives with two lateral apicalcrests .. B.steenisii
15. Plantfloweringup to 11cmheight;connectives lackingapicalcrests B. wallichii
336 BLUMEA Vol. 41, No. 2, 1996
Theidentificationofthesesaprophytic Burmanniaspecies is complicated by their
highlyreduced structure,andby the variationapparentin all thediagnostically im-
portantcharacters, including: thesizeand shape oftheinnerperianth segments; the
widthoftheperianth wings;andthesizeandshape ofthedorsaland ventralstaminal
connectiveappendages. For mostspecies, theclassification has also necessarily been
basedona very smallnumberofcollections.Although theFloraMalesianakey has
beenamendedtoincludeB. wallichii, thismust thereforestillberegarded as prelim-
inary untilamore detailedrevision is undertaken,enabling anappreciation ofthepat-
tern ofvariationinthespecies over theirentiregeographical distributions.
TAXONOMIC TREATMENT
Burmanniawallichii (Miers) Hook.f.
Burmannia wallichii (Miers)Hook,f.,Fl.Brit.India 5(1888)666;Wright, J.Linn. Soc. 36 (1903)
5; RidL,Mat. Fl. Mai. Pen. 2(1907)71;Gagnep.in Lecomte, Fl.Gen. Indo-Chine 6 (1908)
21;RidL,Fl. MalayPenins. 4(1924) 305; Jonker,Meded. Bot.Mus. Rijks Univ. Utrecht 51
(1938) 145; R.M.K.Saunders, Gard. Bull., Singapore(in press). — Gonyantheswallichii
Miers,Trans. Linn. Soc. 18(1841)537; Benth.,Fl.Hongkong.(1861)364. —Type: Wallich
399 (BMlecto;B,G isolecto), Kilaben,Burma.
Burmannia griffithii Becc., Malesia 1 (1877)254. —Type:Griffith5592 (CAL,P,W),Burma.
Saprophytes withhighly reduced colourless leaves; flowering at 4.5-6.5-11 cm
height. Stemsimple, filiform.Basalrosette ofleavesabsent. Stem leavesachloro-
phyllous, ± appressed, scale-like, subulate-triangular, with acute apex, sometimes
keeled; 1-2-2.8 mmlong. Bracts lanceolate, 2.5-4 mm long.Flowers solitary or
occasionally in pairs or threes, subsessile, 6-7—9.5 mm long; perianth white or
bluish; perianth tube cylindrical, c. 3 mmlong; outer perianth lobestriangular with
obtuseapex,to c. 1 mmlong; innerperianth lobesminute, orbiculate, withrounded
apex; lateralperianth wings narrow, ±linear, c. 4.5 x0.5 mm;staminal connective
withoutapicalcrests,butwithshortbasal spur; gynoecium as long asperianth tube;
ovary c.2.5 mmlong.Fruitacapsule, dehiscing ± irregularly by transverse splits, n
= 16(Larsen, 1963).
Distribution—India,Burma, Indochina, Thailand, Malay Peninsulaandsouthern
China(Guangdong andHong Kong) (Jonker, 1938).
Ecology —Little is knownoftheecology ofB. wallichii, although it is clearly
saprophytic; itthereforepresumably growson decaying leaflitter, woodor roots in
the deep shadeofwet tropical forests, as isseen withother saprophytic Burmannia
species.
Representative specimens studied: Kerr 926, 2 Jan. 1910, Doi Sootep, Chungmai, Thailand
(BM);Ridley'scollectors.n. [withoutdate],Kranji,Singapore(SING); Wallich399 [withoutdate],
Kilaben,Burma(B,BM,G); Wilford1444,Dec. 1857,HongKong(BM).
ACKNOWLEDGEMENTS
I amgratefultothe directors ofB,BM, C,G,L and SINGforthe loan ofherbarium material,and
ananonymousreviewer forcommentsonthemanuscript.
R.M.K.Saunders: Burmannia wallichii in Malesia 337
REFERENCES
Backer, C.A.,& R.C.Bakhuizen vandenBrink, f. 1968.Floraof Java,Vol. 3.Wolters-Noordhoff,
Groningen.
Jonker,F.P. 1938.Amonographofthe Burmanniaceae. Meded. Bot.Mus. RijksUniv. Utrecht 51:
1-279.
Jonker,F.P. 1948. Burmanniaceae. Flora Males.,ser.I,4(1): 13-26.
Larsen,K. 1963.Studies intheflora ofThailand. 14.Cytologicalstudies in vascular plantsofThai-
land. DanskBot.Arkiv 20: 210-275.
Ridley, H.N. 1907.Materialsfor aFloraofthe MalayanPeninsula. Part II.Methodist Publ. House,
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Ridley, H.N. 1924.TheFloraofthe MalayPeninsula,Vol. 4.Reeve,London.
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