87 of character linkage. Kitching et al 1998 stated that the more that characters
become linked, i.e. dependent on other characters, the greater is the departure from independence and consequently the risk that one false homology can obscure
the topologies of true homologies decreased. Composite coding applied in this study was also designed to reduce the
error that extensive amounts of missing data a character state scored as ‘?’ can create in a parsimony analysis Maddison 1993. The fronds architecture of
Diplazium are varying, from simple to quadripinnate. Consequently taxa with
simple, pinnate, bipinnate fronds do not posses any organ that possessed by those with pinnate, bipinnate and tripinnate fronds, respectively.
Character 36. Table 6.1 is an example of composite characters in this study. It was created from the combination of two characters: 1 Lateral pinnae
existnot exist and 2 Shape of lateral pinnae oblong oblong lanceolate elliptical liniery triangular oblong subtringular lanceolate ovate. These two
characters in which the latter is dependent on the former, were combined into a single character with eight character states lateral pinna oblong oblong
lanceolate elliptical liniery triangular oblong subtringular lanceolate ovate organ not exist. This method reduced the numbers of linked characters and
limited the influence of multiple missing characters states on the analysis for previously coded characters ‘lateral pinnae oblong oblong lanceolate elliptical
liniery triangular oblong subtringular lanceolate ovate’ in those taxa which have no lateral pinnae. Maddison 1993 stated that missing character states can
cause difficulties for parsimony analysis if the missing state for the character occurs in more than one clade.
6.3. Character Variation within West Malesian Diplazium
Previous pteridologist worked on Diplazium have summarized the principal characters of the genus Diplazium and identified the important
morphological features in identification and classification. Characters those particularly variable across the taxa and which may be significant in an
evolutionary sense are discussed as follow.
88 a. Rhizome
Most of West Malesian species posses erect rhizome. The appearances of the erect rhizome are varying. The very short and small rhizome are seen in D.
crenatoserratum and D. tomentosum. The stout and medium rhizome are found in
D. dilatatum , D.kunstlerii, D. megasegmentum, D. polypodioides, and D.
subpolypodioides. The stout long rhizome is present in D. esculentum. Some species have sreeping rhizome, such as D. donianum, D. procumbens, and D.
subvirescens Mickel 1974 presumed that the main lines of the ferns begun with
probably creeping rhizome. Thus the erect rhizome is regarded as derived. Figure 6.1. showed the rhizome patterns of Diplazium.
b. Scales and Hairs Scales in Diplazium are varying. As showed by Holttum 1940, 1966,
Kato 1977, 1995, and Tagawa Iwatsuki 1988, scales are very important characters in determining species in Diplazium Figure 6.2.. The scales mainly
attach on upper of the rhizome and stipes. On some species scales are also present on the rachis or the costa, but in smaller size than those on the rhizome
and stipes. Scales are generally linear lanceolate to obong lanceolate. Rounded or ovate scales are present on the projections of a muricate stipe such as in D.
megasegmentum and D. profluens new species proposed, See Chapter 9, D.
kunstlerii , and D. latisquamatum. Rounded or ovate scales which is initially
having a function as an covered organ of spines are seen on the stipe of D. spiniferum.
Scales are generally attached with a basal point. Some species with rounded or ovate scales, such as in D. kunstlerii, D. latisquamatum, D.
megasegmentum and D. spiniferum, have scales with a subbasal point attachment
Figure 6.2.g. in this Chapter; Chapter 9. Scales with a subbasal point attachment may be derived. Dickason 1946 presumed that a scales with a basal point of
attachment may be more easily derived from a hair than one with broad base or one peltately attached.
Diplazium scales are entire or toothed, with tooth consisting of two
upturned ends of adjacent marginal cells. The marginal may be with thickening brown-black strand or not. Toothed scales may show sharp and blunt teeth,
89 regular or irregular teeth construction, and forked or not forked teeth. The
existence of glandular cell at the marginal scales are important in differentiating among species with entire scales or with blunt toothed scales, such as in D.
tomentosum , D. pallidum and D. spiniferum. Scales with entire margins may be
simpler than those with toothed margins. Because evolution never starts with complex constructions Schölch 2000, the toothed margin scales may be derived.
Figure 6.1. Rhizome appearance of Diplazium. a. short-creeping rhizome of D. donianum
; b. medium-creeping rhizome of D. subvirescens; c. medium-erect rhizome of D. accedens
; d. short-erect rhizome of D. halimunense; e. stout-erect rhizome of D. megasegmentum
.
90 Scale colour are also important in species identification. Scales colour
may be yellowish, pale brown, brown, dark brown to black. For example, black scales of D. meijerii will be differentiate fast this species from its related species,
D. atrosquamatum , that has brown scales.
The taxonomical evaluation of the articulated hairs trichomes in the Athyriaceae
has been conducted by Kato 1973. He summarised that the features of the articulated hairs are important in the classification of Athyriaceae. In the
genus Diplazium, Kato 1972 showed two kinds of articulated hairs, viz. hairs with glandular cells and without glandular cells in Monomelangium pullingeri
that has been proposed to be placed in Diplazium and become D. pullingeri and D. tomentosum
, respectively. There are only several West Malesian species that posses hairs. The hairs are without glandular cells. D. squarrosum posseses
stellate hair. D. tomentosum shows simple articulate hairs densely covered stipe, rachis and costa. D. crenatoserratum posseses simple articulated hair sparsely on
stipes when living and then it will be scarsely found on dried material. c. Stipe
Diplazium stipe is not swollen and becomes gradually thicker downwards.
The stipe is generally green. The stipe anatomy of some species of Diplazium has been studied by Tardieu-Blot 1932, Bir 1962, 1969, and Kato 1972. Leaf
traces are binary. The xylem of a leaf-trace is the same hippocampus-shaped bundle in transaction See Chapter 4. In this study the anatomical characters of
Diplazium were no used in phylogenetic analysis, because most of species
examined were based on only herbarium specimens. Stipe characters used in this study were only those from the gross
morphology, such as the size, colour, and the existence of multicellular hairs, scales, protuberances and spine Figure 6.4.. Most of Diplazium posses scales
only. Multicellular hairs and scales are seen in D. crenatoserratum, D. silvaticum D. tomentosum
. The multicellular hairs in D. crenatoserratum and D.silvaticum are usually only seen in living plants, they are fallen when dry. Whereas in D.
tomentosum the multicelullar hairs can be seen both in living plants and dried
materials. The existence of stellate hairs and scales on the stipes and rarchis of D. squarrosum
make this species is very distinct among the West Malesian
91 Diplazium
. Green protuberances are seen in D. accedens var accedens and D. accedens
var. swartzii. Spines are present in D. accedens var. spinosum and D. spiniferum
.
Figure 6.2. The variation of scale shapes in Diplazium. a. D. halimunense; b. D. tomentosum; c. D.. silvaticum var. silvaticum; d.. D. esculentum; e. D. petiolare; f. D.
batuayauense ; g. D. spiniferum; h. D. sorzogonense; i. D. malaccense; j. D. donianum; k.
D. silvaticum var. pinnae-ellipticum; l. D. angustipinna.
92
Figure 6.3. Margin of scales. a. entire with glandular cells and irregular thickening black strands D. atrossuamatum; b. margin entire without glandular cells and
thickening black strands D. cumingi; c and d. margin sharply toothed with regular thickening black strands c. D. subalternisegmentum , d. D. simplicivenium; e. margin
entire with glandular cells and thickening dark brown strands D. sorzogonense; f. margin sharply toothed irregularly with irregularly thickening black strands D.
halimunense
; g. Margin with densely glandular cells without thickening black strands D. batuayauense; h. margin entire without thickening brown or black strands D.
malaccense ; i. margine toothed without thickening black strands D. petiolare.
93 When old or in dried specimens, stipes may glabrous, sparsely or densely
scales throughout its length. Chistensen 1911 said that the best and most constant specific characters is to be found in the dermal appendages, hairs and
scales. A glabrous shoot may be thought ofas more primitive than one having a potentiality for the developmental of dermal outgrowth Dickason 2007.
Figure 6.4. Stipes appearances of Diplazium. a. Stipes densely scales D. simplicivenium
; b. stipes dark green, covered sparsely by rounded-ovate scales, scales fallen when dry D. spiniferum; c. Stipes covered by green protuberances D.accedens
var. swartzii ; d. stipes spiny, scales fallen when old D. accedens var. spinosum
94 d. Rachis and costa
As showed by Kato 1977, the rachis and costa groove is usually open to admit the groove of leaf axis of lower order. D. accedens, D. crenatoserratum, D.
subserratum, D. tomentosum, D. xiphophyllum have rachis that prominently raised
above with shallow grooves and their grooves are U-shaped with flat base Chapter 4., Figure 4.2.. The appearance of rachis groove would give more
informative parsimony characters. The cross section of rachis are generally similar to the cross section of stipes near lamina. Unfortunately, in this study,
anatomical data of the cross section of stipes near lamina were only obtained from 27 species due to the lack of the living collections in most species.
Therefore grooves characters on rachis or stipes did not used in this analysis, because they would cause many missing data on many species.
Generally, rachis are glabrous. Some species has fibrillose or sparsely minutely scales or spiny. Fibrillose rachis seen in D. sorzogonense and D.
loerzingii. Spines are present in D. accedens var spinosum and D. spiniferum.
Because the existence of fibrillose scales or spine are only in few species, in this study the rachis and costa characters were not used.
e. Fronds architecture Fronds architectures in Diplazium are varying, they are simple to
quadripinnate. Most of West Malesian species have pinnate to bipinnate fronds. Simple fronds is seen in D. subserratum, but in very young fronds are pinnate
Figure 6.5.. Deeply pinnatifid fronds, sometimes with one pair of free to numerous segments, are seen in D. fuliginosum, D. lomariaceum and
D. porphyrophyllum. D. cordifolium
has both simple and imparipinnate fronds. Imparipinate fronds are in D. aequibasale, D. bantamense, D. lobbianum D.
donianum, D. halimunense a new species proposed in Chapter 10, D. riparium,
D. xiphophyllum , and D. wahauense. The intermediate fronds between pinnate
and imparipinnate is seen in D. pallidum. Bipinnate-tripinnatifid fronds are present in D. umbrosum. Tripinnatifid fronds are seen in D. megasegmentum, D.
melanolepis and D. subpolypodioides. In D. subalternisegmentum fronds are
tripinnate. Tripinnatifid to quadripinnate frond is seen in D. moultonii.
95
Figure 6.5. Frond architectures of Diplazium. a. b. D. subserratum, a. juvenile fronds, b. adult fronds; c. pinnate frond of D. silvaticum var. pinnae-ellipticum; d. imparipinnate frond of D.
donianum ; e. bipinnatifid frond of D. spiniferum; f. bipinnate frond of D. esculentum.
96 e. Venation types
There are two kind of venation, viz. free venation and anastomosing venation Figure 6.6.. Free venation type may be forked or pinnate in the lobes.
Generally forked veins are present in the species with simple to simply pinnate fronds or in species that have intermediate fronds between simpli pinnate-pinnate
such as D. subserratum, D. aequibasale, D. bantamense, D. lobbianum, D. riparium
and D. pallidum. Veins may forked once or more. Whereas pinnate veins are seen in the species with pinnate to quadripinnate such as D. petiolare, D.
silvaticum , D. malaccense, D. dilatatum, D. polypodioides and so on.
Reticulate venations are seen in D. accedens, D. angustipinna, D. esculentum, D. cordifolium, D. cumingi, D. insigne, D. megasimplifolium
a new species proposed, See Chapter 9, and D.squarrosum. There are some species that
generally have free venation, but occasionally show veins uniting at margin such as in D. fraxinifolium, D. riparium and D. xiphophyllum.
Kato 1977 showed two types of reticulate venation in Diplazium, goniopterid venation and sagenoid venation. In West Malesian Diplazium,
goniopterid venation are seen in D. esculentum, D. accedens, D. insigne and D. squarrosum
.. Meanwhile the sagenoid venation are present in D. angustipinna, D. cordifolium, D. cumingii
and D.megasimplifolium. Anastomosing venation in Ophioglossum is believed advanced, free
venation in other genera as primitive Kato 1987. However the development of anastomousing venation from free venation may be parallel, it may evolved in
different phyletic lines. f. Sori
Diplazium sori are dorsal on the vein and linear, elongated along veins
with lateral indusium Figure 6.6.. They are either single Asplenoid or double Diplazioid. Asplenoid sori generally occur along the acroscopic side of a vein
and Diplazioid sori are beared on both sides of the basal acroscopic vein. As stated by Bower 1928, Holttum 1947, and Kato 1977, Asplenioid sori are
produced by abortion of the shorter arm of J-shaped sori along the basiscopic side of a vein, in view of all intermediate forms. Bower and Holttum interpreted that
Diplazioid sori are produced by interruption of horseshoe- or J-shaped sori at the
97 distal end. Kato 1977 added that the interpretation of Bower and Holttum may
lead to the possibility of Diplazioid sori on higher veins in addition to the basal acroscopic vein. Diplazioid sori bifurcate along the bifurcating basal acroscopic
vein, as in Athyrium and Deparia. As pointed out by Kato 1977 Diplazioid sori are not regarded as a morphological unit, but each one of a pair as a mere single
Asplenioid sorus facing either the costule or costa.
The position of sori in Diplazium is important in species determination. Mainly, there are two type of sori position, viz. subcostular sori and medial sori.
The subcostular sori can be divided into two group, viz. that running from until touching midveins and those reaching at proximal end. The medial sori may not
touching midvein inframedial or almost perfectly medial. Most of West Malesian Diplazium posses subcostular sori.
Generally sori are not impressed, but some species show impressed sori. The impressed are present in D.poiense, D. sorzogonense, and D. subserratum.
The existence of impressed sori on D. sorzogonense becomes one of the diagnostic characters to differentiate this species from D. speciosum.
In the past, a number of phylogenetic schemes presented for ferns was based great stress on the position of the sorus marginal vs. dorsal with only rare
instances of changing from one to another, as in Bower’s “phyletic slide” of Bower’s scheme 1923-28. Now, this do not faithfully represent all the diversity
within the ferns, the shift from marginal to dorsal sori occurring several times Mickel 1974. In the case of soral position on Diplazium, It is not known
whether those subcostular sori are advance or primitive. g. Indusia
Most species have firm and persistent indusia. Some species posses very thin indusia and fragile, such as D. procumbens.
Generally, the indusia is concolour, there is not color difference between attachment side and margin. But some species posses distinctive indusia, marginal
indusia are paler than those at the attachment side, e.g. in D. cumingii and D. loerzingii
new species proposed, see Chapter 10.
98
Figure 6.6. Venation types of Diplazium. a-c. Free venation, a. vein pinnate in the lobus, veinlets simple, D. batuayaense; b. vein once forked, D. pallidum var. montanum;
c. vein forked 3-4 times, D. donianum; d-e. vein anastomousing, d. goniopteris venation, D.accedens
; e. sagenoid venation, D. megasimplifolium.
99
Figure 6.7. Sori variation in Diplazium. a. D. densisquamatum; b. D. cordifolium; c. D. accedens
; d. D. xiphophyllum; e. D. megasegmentum; f. D. subvirescens; g. D. asymmetricum;
h. D. esculentum.
100 Indusia may be entire or not. It would be one of the important characters
in species determination. Most of Diplazium have entire indusia. Generally, entire indusia are seen in species with simple to pinnate fronds, such as D.
suberratum, D bantamense, D. cordifolium, D. lobbianum, D. pallidum, D. riparium, D. silvaticum, and D. wahauense
. Whereas non entire indusia toothed or fringed or lacerate are found in species with bipinnate fronds, such as D.
atrosquamosum, D. beamanii, D. betimusense, D. esculentum, D. Kunstlerii, D. laevipes,
and D. meijerii.
6.4. Materials and Methods 6.4.1. Taxon Sampling
