A monograph of the fern genus Thylacopteris (Polypodiaceae)

14 Pages·1994·2.1 MB·English

by  Rödl-Linder, G

BLUMEA 39 (1994) 351-364
A monographof the fern genus Thylacopteris
(Polypodiaceae)
G. Rödl-Linder
Rijksherbarium/Hortus Botanicus,P.O.Box9514,2300 RALeiden, TheNetherlands
Summary
This studydeals withthe systematics ofthefree-veined Polypodiaceaelacking any soralparaphyses
and representedonlyin thepaleotropics.Itincludestherecognitionanddescriptionoftwo species of
ThylacopterisKunze exJ.Sm.afull synonymy andadiscussion ofits systematic position.
Introduction
This study concentrates on the analysis oftwo species earlierreferredto the genus
Polypodium L. (sensu lato) withfree, once forking veins. John Smithestablished
thegenusThylacopteris toaccommodateonly onespecies, T.papillosa. Asthetax-
onomic history shows, not much attentionwas given to this genus.Some authors
assume analliancewithPolypodium L.(sensu stricto)and Goniophlebium (Blume)
Presl, others declareitssystematic position as uncertain.
Inordertoclarify theidentity andtounravelthesystematic position ofthis genus
ananalysis ofcharacters was undertaken. They concern the morphology ofthema-
ture sporophyte, with respect tothe rhizome, therhizomescales, thegross morphol-
ogy, the venationpattern, the indument, the sori, the sporangia, and the spores.
Microscopical andsubmicroscopical featureswere included.Several ofthesecharac-
ters were studiedin detailforthis groupforthefirst time.Characterstatessuch as
the articulationofthepinnae withthe rhachisandtheabsence ofany soral paraphy-
ses confirm its generic status and justify the retentionofthe genus.Within Thyl-
acopteris two species arerecognised, T. diaphana having been neglected by most
authors. The resultsof thecharacter analysis were compared withcorresponding
detailedinformationavailableonGoniophlebium (Blume) PreslandPolypodium L.
(s.s.)(Rodl-Linder, 1990).Anumberofcharacterssuggestarelationwiththegenus
Goniophlebium (Blume) Presl,especially withthe(partly) free-veinedspecies ofthis
genus,rather thanwith any othergenera.
Geographical andecological particularitieswere investigated. Itwas attempted to
clarifyeventualrelationships alsoincorrelationwiththegeographic distributionpat-
tern.
Inthe taxonomicpart anemendeddescription of thegenusis given. The species
are describedin detailand a listof distinguishing characters foridentification is
provided.A fullsynonymy of concernedtaxa is given andinformationonthedistri-
bution, thehabitatandon otherrelevant observationsisadded.Anindexofthespec-
imensstudied is included.
352 BLUMEA Vol. 39, No. 1/2, 1994
MATERIAL AND METHODS
Dried specimens of c. 200collection numbers, partly withmany duplicates, were
studied from the following herbaria(the abbreviationsfollowthe IndexHerbario-
rum): A, BM, BO, GH, K, L, MICH, NY, P, PNH, UC, US. Selected specimens
werealsoexaminedfrom RO.
Foranatomicalstudies, commonmethodsas describedby thepresentauthor(1990)
havebeen applied.
TAXONOMIC HISTORY OF THYLACOPTERIS
Thegenus Thylacopteris was createdby John Smith(1875) to accommodatePoly-
podiumpapillosum Blumeas the only species. As distinguishing characters from
true Polypodium he stressed the deeply impressed sori andthe articulationofthe
lateralsegmentswith therhachis.
Christensen(1934) stressed the resemblanceofThylacopteris papillosa to Poly-
podium vulgare L.andthecloserelationship ofthesebothto Goniophlebium (Blume)
Presl. Considering Thylacopteris diaphana congeneric with T. papillosa, Copeland
(1947) had difficulties to recognise generic characters. Ching (1978) confirmed
Christensen'ssuggestion ofa closerelationship betweenThylacopteris, Polypodium
L.(sensu stricto) andthefree-veinedspecies ofGoniophlebium (Blume) Presl.
Otherauthorssuch as Holttum (1966) and Tryon & Lugardon (1991) preferred
tokeep Thylacopteris within thegenusPolypodium. Tryon & Tryon (1982) placed
Thylacopteris into analliancewithPolypodium andGoniophlebium, however,with-
outaccepting it as a genus.Hennipman etal.(1990) recognises a genus Thylacopte-
ris "thesystematic position ofwhichis stilluncertain", withinthetribePolypodieae.
MORPHOLOGY AND ANATOMY OFTHE MATURE SPOROPHYTE
Characters and character states
Afterthe recognition ofthespecies, analyses ofatotalof65 morphological andana-
tomical characterswereexecuted.Characters were selectedconsidering theirimpor-
tance forcomparison withGoniophlebium (Blume) PreslandPolypodium L. (s.s.)
inordertoelucidatesystematic relationships.
Thirty-six distinguishing characterswererecognised andacertainnumberofchar-
acterstateswereattributedtothem.Adiscussion is given aboutthecomparison be-
tween thetwo species ofThylacopteris and thecharacterstatesrecognised inGonio-
phlebium (Blume) Presl, withspecial referenceto the(partly) free-veinedspecies of
this genus. These are G. manmeiense(Christ) Rodl-Linderand G. microrhizoma
(Baker) Bedd.,twooftheninespecies building theGoniophlebium subauriculatum-
groupwhichis consideredamonophyletic group.Inadditiontherespective character
statesin anAsianrepresentative ofthePolypodium vulgare-complex, P. vulgare L.
var. japonicum Franchet& Savatier(syn. PolypodiumfaurieiChrist) are includedin
the comparison. (For furtherdetails onthe descriptions, see Rodl-Linder, 1990.)
Characters arebasedonstudiesofmature sporophytes. They concern rhizomes, rhi-
G. Rodl-Linder: Monographof Thylacopteris 353
zome scales, frondsincluding gross morphology, venationpattern, laminar indu-
ment,soriwithsporangia, andspores.
Rhizome
Distance ofphyllopodia - Thephyllopodia ofThylacopteris are situated 3-12mm
apart. Thisoverlaps withthe valuesin Goniophlebium manmeienseand G. micro-
rhizoma,butis more distantthaninPolypodiumfauriei.
Darkbundlesheaths- Darkbundlesheaths arepresentonly inThylacopteris pa-
pillosa, whilethey areabsentinT. diaphana andthespecies undercomparison from
theothergenera.
Numberofsclerenchyma strands- For Thylacopteris papillosa between 12and
100vlerenchyma strandshavebeencounted, whilesclerenchyma strands areabsent
inrhizomes of T. diaphana. Dark sclerenchyma strandsarepresentin allGoniophle-
biumspecies, varying in numberfrom 1to morethan 100.Sclerenchyma strands are
absentinthe species belonging to thePolypodium vulgare-complex andinall neo-
tropical species withgoniophlebioid venation.
Rhizome scales
Major differencesbetweenthespecies groups havebeen foundconcerning the rhi-
zomescales.
Insertion- Rhizomescales ofbothspecies ofThylacopterisas wellas ofthe(part-
ly) free-veined Goniophlebium species are evenly inserted. ThoseofPolypodium
fauriei are insertedin aninvagination. Bothcharacterstatesare foundinothergroups
ofGoniophlebium.
Colour All species of Thylacopteris and Goniophlebium have brown rhizome
-
scales, whereasinPolypodium faurieithey areorange.
Exposition - Allrhizomescalesare atleastbasally adpressed totherhizome. How-
ever,inboth Thylacopteris species they are apically spreading, as they are inmost
Goniophlebium species. InPolypodiumfauriei the wholescaleis firmly adpressed to
therhizome.
Density - Therhizomescales ofThylacopteris covertherhizomelessdensely than
theydo intheotherspecies undercomparison.
Persistency - RhizomescalesofThylacopteris aredeciduous.Respective species
ofGoniophlebium andPolypodium have persistentrhizome scales.
Dimorphism and general shape - Dimorphism hererefers tothepresence ofmu-
cronate and deltoidrhizomescales only in Thylacopteris diaphana. InT. papillosa
andthe Goniophlebium species under study the rhizomescales are always deltoid.
Theshape oftherhizomescales ofPolypodiumfauriei is broadly deltoid.
Apex shape - Theapexofdeltoidor mucronaterhizomescales is acute oracumi-
nate (Fig. la-d). InPolypodium fauriei theapex ofthe rhizomescales is rounded.
Shape ofauricles- Auricles areroundexcept in Goniophlebium microrhizoma
where they are pointed.
Attachment- Generally rhizomescales ofallspecies belonging tothegenusGonio-
phlebium as wel' as to Thylacopteris are pseudopeltately attached (Fig. la-d). Pel-
tate attachmentis afrequent characterstatein goniophlebioid species fromtheneo-
tropics whichareretainedinPolypodium.
354 BLUMEA Vol. 39, No. 1/2, 1994
Fig. 1.Thylacopterisdiaphana(Brause)Copel.(Brass24996).a.Deltoidrhizome scaledetail,x80:
perfoliate, auriclesoverlapping,basalcells puzzle-shaped;b. deltoidrhizome scaleoudine;c.mucro-
naterhizome scale detail,x 80:perfoliate,auricles cordate,marginalcells puzzle-shaped; d.mucro-
naterhizome scale outline;e. detailofpuzzle-shapedcell walls with the innerlayer warty, x550.
G. Rodl-Lindcr: Monographof Thylacopteris 355
Indexlength/width - Thelength/width ratiois clearly lowerin rhizomescalesof
Polypodium faurieithan itis intheotherspecies undercomparison.
Clathrationofcell walls- RhizomescalesofPolypodium fauriei are completely
opaque,whilemostoftheircellwalls arethickened inThylacopteris and Goniophle-
bium.
Clathratecellwallsinnerlayer- Obviously arare appearanceis awarty state of
thethickenedinnerlayer (Fig. le).Itispresentinboth Thylacopteris species, how-
ever never inGoniophlebium norinPolypodium. Ithas earlieronly beenobservedin
onespecies ofMicrosorum, viz. M.spectrum(Kaulf.) Copel. (Bosman, 1991).
Shape ofcellsbasally- ThischaracterofThylacopterisrepresentsan unique state.
Thecellsofthebasalpartofthescales are clearly jigsaw-puzzle-shaped (Fig. la-e).
Thishasnot beendescribedfromany otherspecies of thefamily. SomeMicrosorum
species have slightly wavy anticlinalcell wallswhichare, however,not reallyjigsaw-
puzzle-shaped. In Selliguea feei Bory asimilarcell shape ispresent, but thescales
areotherwisevery different.
Clathratemarginal protrusions- Themarginoftherhizomescales inGoniophle-
biumis ciliate, i.e. clathratemarginal protrusions arepresent. Such protrusions are
very shortin Thylacopteris(Fig. la, c) andabsentinPolypodium (s.s.).
Rhizoid-likesurfacehairs- Rhizoid-likesurface hairsonrhizomescales areab-
sent in Thylacopteris, but presentinGoniophlebium manmeiense, G. microrhizoma
andinPolypodiumfauriei.
Fronds
Gross morphology
Texture- Thetexture offrondsof Thylacopteris is transparently membranaceous.
In Goniophlebium itis generally thinherbaceousandinPolypodium (s.s.) firmher-
baceous.
Maximum length ofblade- With a length of59 cm, the longest fronds have
been encountered in Thylacopteris, while fronds ofPolypodium fauriei do not
exceed 32cm.
Lateral segmentarticulation- The lateralsegments are in all species concerned
deeply divided, almostto therhachis. Thylacopteris diaphana andT.papillosa show
a unique characterstatehere. Arudimentary abscission layerindicatesanarticulation
ofthelateralsegmentswiththerhachis(Fig. 2).
Lateralsegments distance- Lateralsegmentsare closesttoeach otherinspecies
ofThylacopteris andwidestapartinPolypodium fauriei.
Venationpattern
The species undercomparison herehavea freevenationpatternin common.The
veins are usually easily seen, but inPolypodium fauriei thevenationis sometimes
indistinctduetothefirmtexture ofthelamina.
Free veins - Inspecies of Thylacopteris the freeveins may be simple, but are
mostly once-forked.In Goniophlebium manmeiensethey areonce-forked, whereas
in G. microrhizomaas wellas inPolypodium fauriei theyare twice-forked.
Areolae- Goniophlebioid areolaewithfreeincludedveinsare sometimespresent
in Goniophlebium microrhizomaandabsentintheother species understudy.
356 BLUMEA Vol. 39,No. 1/2, 1994
Fig. 2. Thylacopterispapillosa (Blume) Kunze ex J.Sm. (Jermy 13985),part ofafertile frond,
detailofthe uppersurface ofthree middle pinnae,articulation ofthepinnaewith therhachis indi-
cated;x 3.2.
Laminarindument
Glandularhairsarepresentonthelaminaandpetioles ofallspecies ofthefamily
Polypodiaceae. However, there are differences in the length andin the numberof
terminalglands. Itseems thatThylacopteris hasonly 2-celledglandular hairsinclud-
ing one terminalgland, whereas in Goniophlebium andPolypodium longer hairs
withsometimes2 or 3terminalglands occur.
Laminar/petiolar acicularhairs- Acicularhairs areabsentinThylacopteris as well
as in thefree veinedspecies ofGoniophlebium. In Polypodiumfauriei they arepres-
ent. They maybepresentorabsentinotherspecies ofGoniophlebium.
Sori, paraphyses andsporangia
Soriare arranged uniserialateithersideofthemain vein,terminally atafreevein.
Iftheveinis once forked, thenthesorus is locatedattheacroscopic branch.InPoly-
podiumfauriei theveinis forkedtwice. Inthiscase theposition ofthesorus isatthe
endoftheacroscopic branchsituatedclosertothemainvein.
Relationof thesori tothesurfaceofthelamina- Thylacopteris diaphana hassuper-
ficialsori, as do thespecies oftheothergeneraunder comparison. In T.papillosa the
soriare deeply sunken. Species of theGoniophlebium percussum-grouphavemore
orless sunkensori, but differinmanyotheraspects from Thylacopteris.
Shape ofthesori - Concerning this characterGoniophlebium microrhizomawith
slightly ovalshaped sori represents anexception. Thecommonstateis aroundshape.
G.Rodl-Linder: Monographof Thylacopleris 357
Receptacular hair-likeparaphyses - Receptacular hair-likeparaphyses were found
inallspecies ofGoniophlebium andPolypodium (s.s.)but are absentin Thylaco-
pteris.
Hair-likeparaphyses branching fromsporangial stalk- Theseepisporangial struc-
tures areabsentin Thylacopteris andPolypodium fauriei,butpresentin Goniophle-
biummanmeienseandG. microrhizoma.
Totalannulus cells ofthe sporangium - The annulus ofsporangial capsules of
Polypodiumfauriei consists of21-25cells, whileall otherspecies undercompari-
son havea totalofonly 17-20annuluscells. However, other Goniophlebium spe-
ciesalso havehigher numbersofannulus cells.
Length ofthesporangial capsule - WithinthegenusGoniophlebium, G. manmei-
enseandG. microrhizomahaverelatively smallcapsules. Capsules of Thylacopteris
withalength ofc. 325 pm reachthe upperlimitoftherangefound forPolypodium
fauriei.
Spores
Sizeofthespores - Corresponding toasmallersize ofthesporangial capsule, the
sporesofthefree-veinedspecies ofGoniophlebium are also smallerthanthose of
Thylacopteris andPolypodium fauriei.
Fig. 3.Thylacopterisdiaphana(Brause)Copel.(Brass12838).a.Lateralview:exospore pusticulate,
laesura0.5x lengthofspore; b.detail:perispore shallowlyreticulate,globulesmanyinvarioussizes.
—Thylacopterispapillosa(Blume)Kunze ex J.Sm.(Johansson c.s.84); c. lateralview: exospore
smooth,laesura0.7 xlengthofspore; d. detail:perisporeplain, globulesmanyin varioussizes. —
Scalebars: a& c=10µm; b& d=5µm.
358 BLUMEA Vol. 39,No. 1/2, 1994
Perispore surfaceornamentationseenwiththeSEM(x 5000) -Whilsttheperispore
of Thylacopteris papillosa is smooth (Fig. 3c, d), the perispore of T. diaphana is
shallowly reticulate (Fig. 3a,b), the one of Goniophlebium manmeiense is granu-
late,andslightly undulateinG. microrhizomaandPolypodiumfauriei.
Globules ontheperispore - Whilstthereare always (few to) manyglobules, i.e.
spherical deposits, presenton thesporesofThylacopteris, these are usually absentin
theother species undercomparison.
Surface ornamentationofthe exospore - The smoothcondition, presentinThyla-
copterispapillosa, has beenfound as wellintheGoniophlebiumpercussum-group.
The othertaxa undercomparison show somekindofexospore ornamentation, i.e.
slightly pusticulate or colliculateandverrucate. Theverrucate exosporeis quitedis-
tinct, showing a decreasein thesizeofverrucae towardsthedistalpole.
MONOPHYLY AND SYSTEMATIC POSITIONOF THYLACOPTERIS
Delimitationof thegenus
One characterin the original description (Smith, 1875) hasbeen overlooked by
all laterauthors whocommentedonthis genus. Atfirst itappearsconfusing toread
"fronds pinnatifid laciniaearticulate withthe rhachis." One could imagine
... ...,
thesetwo terms as contradictory. The articulationofthelateralsegments with the
rhachis obviously refers to arudimentary abscission layer presentbasally between
thepinnae, which breaksandfacilitates aseparation ofthepinnae exactly along the
rhachis. In fact, this predetermined breaking point is absentin other free-veined
Polypodiaceae, e.g.species ofthe Polypodium vulgare-complex andthe(partly)free-
veinedspeciesofGoniophlebium.
The deeplyimpressed receptacles are emphasised in allrelevantpublications, even
though they arepresentonly inoneofthetwo species ofThylacopteris. One species
ofthegenus Goniophlebium, G. mehibitense(C. Chr.)Parris, shares this character
state, butisotherwisecertainlynot closely relatedto Thylacopteris papillosa. Chris-
tensen (1934) didnot findany character, thefreeveins excepted, bywhich T.papil-
losa differs fromseveral Malayan species ofGoniophlebium withimmersedsori.
According to him,itstands inrelationto suchspecies exactly asPolypodium vulgare
stands totheAsianspecies ofGoniophlebium withsuperficial sori. Herethe degree
ofimmersionofthe soriis not considereda usefulcharacter to recognise relation-
ships.
Thethird distinguishing charactermentionedby John Smith(1875) is thefree,
once-forkedvenation.Holttum(1966) states: "In Malayawe haveonespecies with
freeveins."He doesnot takeinto accounteitherThylacopteris diaphana or Gonio-
phlebiummanmeiense.
Inadditiontothe freevenationandthearticulationofthelateralsegmentswiththe
rhachis, the presentstudy revealed theimportance ofothercharacters. In Thylaco-
pteris thecell walls atthebaseofthe rhizomescalesare jigsaw-puzzle-shaped and
theirinner, thickened layer is warty (Fig. le). Receptacular paraphyses are totally
absent. Thesecharactersare consideredgeneric anda monophyly of thegenusThyl-
acopteris isassumed.
G. Rodl-Linder: Monographof Thylacopteris 359
Delimitationofthe species
Due to the freevenationcombinedwith othercharacters, as elucidatedabove,
Thylacopterispapillosa hasalways beenaccepted as a distinctspecies. Brausestated
in hisoriginal description ofPolypodium diaphana thesimilarity with P.papillosa,
mentioning thesuperficial situationofthesori as theonly difference.Copeland (1947)
in additionstressed thesclerenchyma strands, whichheconsideredas "merely indi-
cated" inThylacopteris diaphana. Inthisstudy sclerenchyma strands in therhizome
ofT. diaphana have notbeen found. According to Copeland (1947), "this species
couldbeleft inPolypodium, ifitwere consideredbyitself."The present study re-
vealedsomemorespecific characters: darkbundlesheathsarepresentin therhizome
of Thylacopteris papillosa, whilstthey areabsentin T. diaphana. The spores ofT.
diaphanahaveashorter laesuraandashallowly reticulateperispore (Fig. 3b), while
theperispore ofT.papillosa is completely smooth (Fig. 3d). Considering the geo-
graphicrestriction, thespecific identity ofT. diaphana isrecognised.
Systematicposition ofThylacopteris
Afterdetailedmorphological studies, thecloserelationship between Thylacopteris
andGoniophlebium suggested by Christensen (1934), Ching (1978) and Tryon &
Tryon (1982)is confirmed.The (partly)free-veinedspecies ofGoniophlebium are in
gross morphological aspects quitesimilarto thespecies understudy and therefore
oftenmisidentifiedas such.Themaindistinguishing characterstates are thearticulate
pinnae (Fig. 2),theabsenceofsoralparaphyses andthejigsaw-puzzle-shaped, warty
cellwalls oftherhizomescalesin Thylacopteris (Fig. 1).
Thegeographical distribution and several morphological characters suggest a
closerrelationship with Goniophlebium thanwithPolypodium. Thesecharactersare
thedistance between thephyllopodia, the attachment, shape and clathrationofthe
rhizomescales, thevenationpattern,andthesurface ornamentationoftheexospore.
TAXONOMIC PART
Presentationofdata
Sincethegenus Thylacopteris isrepresented by only two species, thekey tothe
species isreplaced by a listofdiagnostic characters. Afull synonymy is given for
eachspecies. Selectedliteratureis included.The description ofthespecies refers to
characters recognised only in dryherbariumspecimens ofadultsporophytes. Living
materialhasnotbeenexamined.Informationonthehabitathasbeentakenfromher-
barium labels.Notes areaddedforspecial remarksandadditionaldata(e.g. numbers
ofspecimens seen), whennecessary. Drawings andphotographs illustratethe most
important details.
THYLACOPTERIS
Thylacopteris Kunze exJ.Sm.,Hist.Fil. (1875)87;Kunze apudMett.,Farngatt.Polypod. (1856)
57,nomen; C.Chr. & Holttum,Gard. Bull. Sing.7 (1934) 304; Copel.,Gen. Fil. (1947) 181;
Hennipmanin Kramer etal„Pteridophytes and Gymnosperms 1 (1990)228. —Polypodium
subg.Ctenopteris (Blume)J.Sm., J.Bot. 3(1841) 394. —Typespecies; Thylacopterispapil-
losa (Blume)Kunze (basionymPolypodiumpapillosumBlume).
360 BLUMEA Vol. 39,No. 1/2, 1994
Moderate-sized.Rhizome long creeping, terete, 2-6 mm in diam., light brown,
clothedwithscales, phyllopodia moreor less prominent, 0.5-6(-12) cm apart; anat-
omy: ground tissueparenchymatous, numberofvascular strands4-14, related to
diameterofrhizome, arranged in aregular circle, bundle sheathspresentorabsent,
black sclerenchyma strands longitudinal, scattered in theground tissue, presentor
absent.Rhizome scales evenly inserted, dullbrown, adpressed or apically spreading,
quite densely set, deciduous,pseudopeltate, deltoidormucronate,upto6.5 mmlong,
apex acute, rarely acuminate, auriclesround, cells light yellow, clathrationof cell
wallspresent,closetostalk absent, atbasalandcentralpart puzzle-shaped with wavy,
anticlinalwalls, atapical partrectangular; innerlayer ofthickenedcell wallswarty,
clathratemarginal protrusionsabsentorsometimes merely indicated, marginal gland
only apical.Fronds monomorphic, articulatetorhizome, petiolate, stipe glabrous or
sparsely scaly, in cross section near base 0.8-3.5 mm across, index length of
stipe/length ofblade0.2-0.6, blade membranous, index length/width 3.6-11.2,
equally wide allalong blade or somewhatwiderabovebase, pectinate, lateral seg-
ments separated fromtherhachis by whatpossibly is anabscissionlayer, inanangle
of(80-)90° towardstherhachis, numberrelativeto length ofblade, linear, apically
obtusetoacute, marginentire, crenate orserrate,lowermost segmentsrarely slightly
reducedand/or deflexed, apical segmentscontinuously reduced inlength, terminal
segmentadnateconformtolateralsegmentsorcaudate.Laminarindument:glandular
hairsrarely present, 2 cellslong with 1or2 terminalglands. Stomata(co-)polocytic.
Veinsfree,simple or once-forked, excurrent withterminalhydathodes. Sori exindu-
siate, uniserial ateach side of costa,situated medially between costaand margin,
superficial or deeply sunken,on hydathodes terminalonan acroscopic vein,round,
0.5-1.8mm in diam., receptacular paraphyses absent; sporangial capsule length c.
325pm, indexlength/width 1.1-1.3, annulusvertical, induratedcells (10 or) 11 (or
12), cellsin total 18-20, sporangial stalk 2-rowed. Spores bilateral, oblong (polar
view), plano-convex (lateral view), light yellow, laesura 0.5-0.7ofthelength of
the spore, exosporesmooth or pusticulate, perispore thin,surface smooth or shal-
lowly wrinkled, globules fewor manyinvarioussizes.
Chromosomes- n= 35, 36, 37.
Distribution- Malesia; Sumatra, PeninsularMalaysia, Borneo, Java,Philippines,
Celebes, Lesser SundaIslands, Moluccas, NewGuinea.
Habitat&Ecology - Primary forest, creeping, epiphytic, epilithic or terrestrial;
shaded;altitude(0-)500-1500(-3500) m.
Note- Thename Thylacopteris derives fromtheGreekword 'thylacos', meaning
cyst, sack or pouch.
DIAGNOSTIC CHARACTERS OF THE SPECIES
la. Sorideeply embossed, bundlesheathsin rhizomepresent, sclerenchyma strands
in rhizome 12-100, widespread in Malesia, except New Guinea
2.T. papillosa
b. Sori superficial, bundle sheaths in rhizome absent, sclerenchyma strands in
rhizome absent,endemicto New Guinea 1. T. diaphana