110
6.5. Results and Discussion
The eighty eight morphological characters Table 6.1. and Appendix 1. were analysed to determine relationship among the 69 species of West Malesian
Diplazium . The eighty eight morphological characters comprises eighty five
parsimony-informative characters, one constant character, and two parsimony- uninformative characters. The eight equally most parsimonious trees of 1366 steps
produce a Consistency Index CI = 0.24, Retention Index RI = 0.48, RC = 0.12, and Homoplasy Index HI = 0.75. Figure 6.8. showed the topology of a strict
consensus tree of the eight equally most parsimonious trees of 1366 steps without the high level of Bootstrap value.
Due to the low level of Bootstrap support, it is very difficult to state any statement with confidence about the relationships within West Malesian
Diplazium generated from morphological date derived from unweighted
maximum parsimony analysis. The out group Athyrium anisopterum is separated from the in group without Bootstrap value. The relationships within Diplazium
were also unresolved, without high Bootstrap values but clade that comprised D. silvaticum
and D. petiolare and clade that include D. lomariaceum, D. megasimplifolium
, D. subserratum and D. prophyrorachis with Bootstrap support 65 and 82, repectively.
The lack of support of the monophyly of the genus Diplazium due to the high proportion of homoplastic characters HI = 0.75. Homoplasy – the
independent origin or loss of one or more traits in different organism – can distort the inference of phylogenetic relationship, tying together similar but unrelated
taxa Givnish Sytsma 1997. Although the phylogenetic tree derived from the maximum parsimony was
lack of or weak support, however, it does not indicate that the pattern observed is incorrect. Triono 2006 stated that the lack of or weak support for a phylogeny
does limit the amount of confidence that can be placed in the relationships between taxa and also the conclusions that can be drawn from the inferred
phylogeny. Therefore some clades generated from the phylogenetic analysis of Diplazium
that seems formed from the closely related taxa were discussed below.
111
Figure 6.8. Strict concensus of 8 trees of length 1366 from unweighted morphological dataset comprises 88 morphological characters. Bootstrap support values between 50-90 are given
above line. Only support value above 50 are shown.
112 Two major clades were identified in the morphological parsimony analysis
without well-supported Bootstrap value: Clade I and Clade II Figure 6.8.. Clade I consist of D. fuliginosum, D. lomariceum, D. porphyrorachis, D.
megasimplifolium and D. subserratum in which D. megasimplifolium and D.
subserratum are the most closely related. In this clade D. fuliginosum is at the
base clade and diverse into four species, viz. D. lomariceum, D. porphyrorachis, D. megasimplifolum
and D. subserratum, respectively. Clade II included most of West Malesian species and splited into two clades with very low-supported
Bootstrap value, viz. D. tomentosum alone Clade II.1. and all the remaining species Clade II.2. . In the Clade II.2. D. crenatoserratum is positioned at the
basal clade and diverse into two subclade, the small clade in which composed of D. velutinum
, D.silvaticum and D. petiolare Clade II.2.A. and the large clade Clade II.2.B.
The affinity of D. fuliginosum, D. lamariceum and D. porphyrorachis. In the topological tree Figure 8.6. D. fuliginosum, D. lomariceeum, D.
megasimplifolium, D. suseratum and D. porphyrorachis form a separated clade
from the other West Malesian species and the wo species, D. subserratum and D. megasimplifolium
a new species proposed, see Chapter 9, are the most closely related. The affinity of the two species will be discussed separately below. The
affinity of D. fuliginosum, D. lomariceum and D. porphyrorachis are supported by the share characters as follow: rhizome short-erect, wiry black roots; fronds
narrowly elliptic, deeply pinnatifid or pinnate, apex coadnate, segments numerous, usually very dark green when living; scales abundant on stipe and rachis, narrow,
usually dark and shiny; veins free. Price 1983 stated that D. fuliginosum is one of the most unusual of all diplazia, was not transferred to the genus Diplazium
until recently. This species is strickingly peculiar by the smooth rachis channel without raised sides, uninterrupted by the insertion of pinna-costa. In small
fronds, and distally on large fronds, the rachis is almost flat above. Other features unusual to Diplazium are sori informally extending from costa to margin, and thin
translucent pinna margin. D. lomariaceum is very closely related to D. porphyrorachis
and until Price 1983 distinguished it from D. porphyrorachis, the name seems to have been ignored since Christ himself who described is as
113 Asplenium lamoariaceum
, reduced lomariaceum to porphyrorachis in Ann. Jard. Bot. Buitenz. 15 1898, p.119. Examining many specimens from K, L, MICH,
NY, P, PNH, UC, and US, Price 1983 showed the signs of apparent gene interchange between D. porphyrorachis and D. lomariceium. In relation of the
two species with D. fuliginosum, Price 1983 believed that rather than to D. lomariceum
and D. porphyrorachis, the closest relationship of D. fuliginosum is to D. cumingii
Presl. C.Chr., with which it agrees in dark frond colour and black axis aging to greeyish; axes without cartilaginous ridges; scales on stipe abundant,
dark, entire; and indusia black with very narrow pale brown margin, curling back at maturity; even though D. cumingii is very different in its conform frond apex
and broadly elliptic pinnae. Price 1983 added that almost exactly the same frond form and even margin structure as D. fuliginosum was independently evolved in
the Central American D. harrisonii Bak. C. Chr. which otherwise differs markdedly in scales and the architecture of the axes.
The affinity of D. megasimplifolium and D. subseratum. In the Clade I the closely related between D. megasimplifolium and D. subseratum is not supported
by well-Bootstrap value. The two species possess similarities on characters as follow: lamina simple with cuneate bases, margin entire on lower part, apex
acuminate. However the two species are very different. The lamina of D. megasimplifolium
is elliptic, much wider up to 10.5 cm wide, margin always entire; veins copiously anastomousing up to 45 way of margin. D. subserratum
possess lamina lanceolate, less than 4 cm wide, margin entire to irregularly crenate; veins free. In juvenile stage lamina of D. subserratum is pinnate.
Holttum 1940 presumed that D.subserratum is probably allied to D. lanceum of India and China but is larger, and a shorter rootstock which is more or less with
tufted fronds; the scales also appear to be smaller. The relationship among D. malaccense, D. sorzogonense and D
tricholepis . Of three species, D. malaccense is closest related to D. sorzognense.
Ecologically the two species also grow in similar localities, species of lowland and mid mountain forest in West Malesia. As also stated by Holttum 1940, D.
malaccense is differing from D. sorzogonense in glabrescent stipe and rachis.less deeply lobed pinnae, and sori not at all impressed. Whereas, D. sorzogonense
114 seems to have affinity with D. tricholepis, mainly its fibrillose rachis, in deeply
lobed of lanceolate pinnae, oblong lobes and veinlet number in each lobe. ‘Imparipinnate frond group’. ‘Imparipinnate frond group’ refer to the
clade in the Figure 8.6. that comprises D. aequibasale, D. angustipinna, D. donianum
, D. cordifolium, D. halimunense, D. cumingii, D. subintegrum, D. bantamense
, D. lobbianum, D. fraxinifolium, D. xiphophyllum, D. hottae, D. crameri
, D. riparium, and D. wahauense. The affinity of these species seems to be natural. The affinity among these species are discussed below.
The affinity of Clade D. cumingii. Clade D. cumingii consists of D. cumingii, D. halimunense, D. cordifolium, D. donianum, D. angustipinna,
and D. aequibasale
. In this clade, two pair of species, D. aequibasale and D. angustipinna
, D. cordifolium and D. halimunense, are the closest related, D. donianum
to be the sister clade of D. aequibasale and D. angustipinna, and D. cumingii
at the basal clade. The relationship patterns among the species of Clade D. cumingii
seems unnatural. The similarities on many quantitative characters among these species that seems not to be correlated with their qualitative resulted
the unnatural patterns. The closest relationship of D. aequibasale is to D. riparium or D. wahauense. Morphologically, D. aequibasale is intermediate between D.
riparium and D. wahauense.
The three species share in characters such as lanceolate dark brown entire scales and oblong lateral pinnae with cuneate base
and margin entire. D. angustipinna and D. halimunense should to be closely related to D. cordifolium and D. donianum, respectively. D. angustipinna and D.
codifolium share light brown scales, margin entire with irregularly thickening
black strands, ovate-lanceolate lateral pinna, and copiously anastomousing veins. While D. donianum and D. bantamense share in irregular sharp toothed scales and
ovate-lanceolate pinnae.. The relationship among D. bantamense, D. lobbinaum, D. subintegrum, D.
fraxinifolium , D. xiphophyllum ,D. hottae. D. crameri. The closest relation of D.
lobbianum and D. bantamense and also D. xiphophyllum and D. fraxinifolium are
very reasonable and natural. The two first species share in the following character combination: dark brown toothed scales; pinnae ovate-lanceolate with rounded
base, margin entire or serrate near apex; vein free and forked several times.
115 Meanwhile D. fraxinifolum and D. xiphophylum are in the collection often mixed
due to the misidentification. D. fraxinifolium differs from D. xiphophyllum in lineary lanceolate scales less that 10 mm long, waved-crenate lateral pinnae,
forking type of veins 5-7 times. D. hottae seems to have close relation to D. xiphophyllum
and D. subintegrum. Tagawa 1972 stated that D. hottae is alled to D. subitegrum
. D. hottae differs in: terminal pinna not lobed at the base and similar to upper lateral ones, pinnae apparently entire, venation obscure, sori
narrower. D. crameri is more close to D xiphophyllum, and differs from this species mainly in characters: scales dark brown, pinnae stalked to 1.5 cm long,
ovate-lanceolate, all veins free D. xiphophyllum is occasinolly showing the uniting veins near margin and forked to 2 times.
The affinity of D. riparium and D. wahauense. As explained in Chapter 2, 5 and 9 D. riparium and D. wahauense are morphologically very similar and
closely related Kato et al 1991. Topological tree showed in Figure 8.6. also revealed that the two species are closely related. Thus the statement of Kato et
al 1991 has been verified in this study.
The affinity of D. pallidum and D. prescottianum. The morphological characters between the two species are very similar. Holttum 1940 presumed
that D. prescottianum has close relation to D. pallidum. D. prescottianum differs from D. pallidum in large brown scales. More lobed edges to pinnae, and many
more soriferous veins in each group. Relationship among D. velutinum, D. petiolare and D. silvaticum. In the
topological tree inferred from morphological data the relationshop among D. velutinum, D. petiolare and D. silvaticum
are not resolved because the Bootstrap value is very low 50, but the closest related of D. petiolare and D. sivaticum
are supported Bootstrap value 65. Morphologically, the two species are very similar See Chapter 9. D. petiolare differ from D. silvaticum in characters
combination as follow: D. petiolare has scales linear with distantly teeth and thickening black strand; upper surface of lamina light green when living, pinnae
lobed ¾ way toward costa, upper base not auricle. Whereas D. silvaticum has lanceolate scales with closely teeth without thickening black strands; upper
surface of lamina dark green, pinnae lobed ¼-12 toward costa
116 This result also showed that this phylogenetic tree generated from
morphological data did not support the taxonomical treatment of van Alderwerelt van Rosenburgh 1908. Treating Diplazium into two sections based on the
venation type, Eudiplazium for those having free veins and Anisogonium in which composed of species having anastomousing veins van Alderwerelt van
Rosenburgh 1908, is not natural. In the topology of the phylogenetic tree generated from morphological data in this study showed that the species members
of the two sections are mixed and did not form into two distinct lines. D.
megasimplifolium Anisogonium is included in Clade I in which also composed
of the other species with free veins Eudiplazium. In the Clade II the species with copiously anastomousing veins, D. accedens, D. squarrosum, D.
angustipinna, and D.cordifolium are nested within the free veins species and also
do not fall in one terminal clade. These results suggests that the anastomousing venation pattern in Diplazium may develop in different line. In evolution this
character occurred parallel. Dickason 1946 stated that free and reticulate venation are not two fundamentally different things, but rather that reticulate
venation may develop from the open type wherever a diverging meristimatic center on the margin of the blade primordium meets and merges with an adjacent
center. Comparison between the phylogenetic tree resulted in this study and the
classification of Kato 1977 could not be done proportionally due to the lack living collection in many species Nevertheless, all the 27 species of Diplazium
that successfully examined their groove and vascular bundles characters Chapter 4 could not also be referred to the five Diplazium group of Kato 1977. There
are only two group, D. dilatatum group and D. javanicum group, that could be reffered to West Malesian species. This topological tree showed that the member
of D. dilatatum
group D. batuayauense, D. dilatatum, D. donianum, D. polpodioides, D. sorzogonense, D. subpolypodioides, D. speciosum, D.
spiniferum, D. subserratum, D. umbrosum , and D. xiphophyllum distributed in
many different terminal clades of the main clade Figure 6.8.. It is indicate that Kato’s classification could nod be applied on West Malesian Diplazium.
117
6.6. Conclusions
Kategori