Materials and Methods Conclusions

14

2.2. Materials and Methods

Ecological and distribution data were collected directly in the field in Java, Sumatra and Borneo and information obtained from the specimens examined. Specimens vouchers are housed at Herbarium of Bogor Botanic Gardens BOHB and will be distributed to some herbaria, including Herbarium Bogoriense BO. In addition, some literatures are cited for comparison.

2.3. Results and Discussion

All species of Diplazium grow terrestrially, except D. lomariaceum. It grows both terrestrially and epipetric on wet rocks, in disturbed or secondary forest and primary forest. Most of species are mountain ferns. They distribute from 10 m – to 3400 m above sea levels. The ecology of West Malesian Diplazium for each species is summarized in Table 2.1. The ecology and the distribution of all species are discussed below.

2.3.1. Ecology

Some authors used habit and habitats for classifying ferns. Holttum 1966 classified ferns into 8 groups based on its habit and habitats, namely: terrestrial sun-ferns, terrestrial shade-ferns, climbing ferns, epiphytes of sheltered places, epiphytes of exposed places, rock-ferns and river-bank-ferns, aquatic ferns, and mountain ferns. Edie 1978 classifies the characteristics of ferns from each type of habitat in general: terrestrial shade ferns, terrestrial sun ferns, epiphytes, rock ferns and aquatic ferns. Parris et al 1992 explained the ecological characteristic of ferns growing in Mt. Kinabalu based on its habit and habitats: roadside and thicket-ferns at lower elevations, high-elevation thicket-ferns, tree ferns, ferns of cultivated areas, shade ferns of forest, ferns of mountain ridges, ferns high elevations, epiphytic ferns, filmy ferns, high-elevation and epiphytes. Chin 1997 described habitat of tropical ferns and its diversity and then he recognized six habitats of fern, viz. lowland rainforest, mountain forest, secondary forest, agricultural areas, swamps and open waters, and urban areas. 15 Based on their main habitat, Diplazium can be included into three major groups: dryland, riparian and rheophytic. Rheophytes are plant species which inhabit the beds of swift-running streams and rivers and grows up to flood-level, but not beyond the reach of regularly occurring flash floods van Steenis, 1981. The rheophytic plants are characterized by having particular morphological characters as follow: a narrow lanceolate leves or leaflets; b mattet root systems; c short erect, ascending, or creeping rhizomes tightly attached to streambed substrates; and flexible stems and petioles. Dryland species generally do not occur in the flooded zone where rheophytes occur, while rheophytes do not occur in dryland habitat where dryland plants thrive Imaichi Kato 1997. As pointed out by Imaichi and Kato 1997, there is distinct habitat segregation between rheophyte and dryland species, especially in the humid tropics. Following the definition described by Lincoln et al 1982, riparian means living or situated on the banks of rivers and streams, whereas terrestrial is living habitually on the land or ground surface.

2.3.1.1. Rheophytic of Diplazium

Rheophytic of Diplazium are smallest group of Diplazium in West Malesia. There are only two species reported in this study, viz. D. aequibasale and D. wahauense Table 2.1. and 2.2.. Kato et al 1991 reported three species, namely D. aequibasale, D. wahaunse and D. subsinuatum. The last species however has been moved into Deparia and treated as Deparia lancea Thunb. Fraser-Jenk based on morphology, cytology and molecular characters Sano et al 2000. In this paper D. subsinuatum is excluded. In Sumatra and Borneo, the first species are usually growing on lowland clayey stream-bank, whereas the second species, that is only found in Borneo, growing at streambed in flood zone in lowland. Van Steenis 1981 classifies rheophytes into obligate and facultative, according to preference for rheophytic habitats. In Borneo, many plants of D. esculentum are growing well on river banks in the flood zone, for example at Sungai Joloi track to Batikap, Central Kalimantan. This species may be included in facultative rheophytes. But anatomical observations show that leaves 16 of D. esculentum have poorly developed intercellular spaces of rheophytes Kato Imaichi unpublished, there is no distinct morphological difference between the reophytic and dryland plants. Kato 1991 regarded such species as evolutionarily incipient rheophytes. Kato et al 1991 assumed that most rheophytes are products of primary speciation from dryland mother species. Diplazium wahauense presumably derived from D. riparium, Deparia biserialis and De. confluens from D. petersenii, Phronephrium hosei from P. rhombeum or P. menisciicarpon.

2.3.1.2. Riparian Diplazium

Only few species occur on river banks or stream. They are D. aequibasale , D. riparium, D. fuliginosum, D. lomariaceum and D. porphyrorachis Table 2.2.. However these species do not strictly grow at this habitat. The last three species are more usual growing in dryland of shady ravine in the forest. In Borneo, much of individual plants of D. riparium are also growing well in shady dryland. All species mentioned above, are usually found on lowland mountain forest. Environmental condition seems very important component of speciation in Diplazium although this of course depend upon of how one of species response the ecological change. Diplazium riparium and its closely related species D. aequibasale and D. wahauense may be a good example for it. Kato et al 1991 presumed that D. wahauense may have been derived from D. riparium which occurs in riparian and dryland forest of Borneo. As they explained and supported by this studies see Chapter 8, these two species share black scales, somewhat crisped, entire scales, blackish stipes, dark brown, naked rachises, and imparipinnate leaves with 4 pairs of entire lateral pinnae. Diplazium wahauense differs from D. riparium mainly in its narrow pinnae, which are characteristic of rheophytes.

2.3.1.3. Diplazium in Dryland

Most of Diplazium species are growing terrestrially in dryland forest. Table 2.1. and 2.2.. According to the light intensity, the dryland Diplazium can 17 be divided into three groups: a opened area, b light shady ferns, and c deep shady ferns. The species that adapted to the light intensity are discussed below. a. Opened area ferns D. esculentum usually grows on opened areas. This species grows well at the dump soil of opened areas both in the forest and at the farming areas. Therefore sometimes this species often form small population at the edges of rivers or stream. b. Light shady ferns There are great number of species growing in the light shady area. Some species adapted to very humid conditions and living near streams, such as D. accedens , D. kunstlerii, D. procumbens, D. profluens, D. squarrosum, D. spiniferum, and D. vestitum. The humidity of the air in primary forest near streams is always high, even in the places well away from streams its average is much above that of the open air outsite the forest. Many species are growing well on dry areas, tolerating drier soil and air. They are found further from streams on forested hill slopes, viz. D. asymmetricum; D. atrosquamosum D. bantamense, D. barbatum, D. batuayauense, D. betimusense, D. cordifolium, D. crenatoserratum, D. densisquamatum, D. dilatatum, D. dolichosorum, D. donianum , D. fraxinifolium, D. halimunense, D. hewittii, D. hottae, D. latisquamatum, D. lobbianum, D. loerzingii, D. malaccense, D. megasegmentum, D . meijerii, D. pallidum, D. parallelivenium, D. petiolare, D. poiense, D. polypodioides, D. sorzogonense, D. speciosum, and D. simplicivenium. Shady ferns usually grow more slowly than sun-ferns. The weak light prevents plants to make its carbohydrates fast and the high humidity may make less loss of water and less root activity. However this condition does not prevent many species of Diplazium from attaining a immense size, such as D. accedens, D. dilatatum, D. polypodioides, D. subpolypodioides, D. megasegmentum , and D. sorzogonense. 18 Table 2.1. Classification of Diplazium Based on their main habitat Major Group Species Number of Species Rheophytic D. aequibasale, D. wahauense 2 Riparian D. aequibasale , D. riparium, D. fuliginosum, D. lomariaceum, D. porphyrorachis 5 Dryland D. accedens , D. albidosquamatum, D. angustipinna, D. asymmetricum , D. atrosquamosum, D. bantamense, D. barbatum, D. batuayauense , D. beamanii, D. betimusense, D. christii , D. cordifolium , D. crameri, D. crenatoserratum, D. crinitum, D. cumingii D. densisquamatum , D. dilatatum, D. dolichosorum, D. donianum , D. esculentum , D. fraxinifolium, D. halimunense, D. hewittii , D. hottae, D. insigne, D. kunstlerii, D. laevipes, D. latisquamatum , D. lobbianum, D. loerzingii, D. malaccense, D. megasegmentum , D. megasimplicifolium, D. melanolepis, D. meijerii , D. moultonii, D. pallidum, D. parallelivenium, D. petiolare , D. poiense, D. polypodioides, D. prescottianum, D. procumbens , D. profluens, D. riparium, D. silvaticum, D. simplicivenium , D. sorzogonense, D. speciosum, D. spiniferum, D. squarrasum , D. subintegrum, D. subalternisegmentum, D. subserratum , D. subvirescens, D. tomentosum, D. tricholepis, D. umbrosum , D. velutinum, D. vestitum, D. xiphophyllum 64 c. Deep shady ferns. Many species are adapted to deep shady areas, such as D. albidosquamatum, D. angustipinna, D. beamanii, D. christii , D. cumingii, D. fuliginosum, D. laevipes, D. lomariaceum, D. moultonii, D. poiense, D. tomentsum, and D. umbrosum. Therefore they are nearly all have much thinner fronds than the light shady ferns. The deep shady ferns species do not need to be tough to avoid being shriveled by the sun’s heat. These species do not need to store water as much as some light shade ferns do. The deep shady ferns usually also show more dark green or blue metallic fronds than the light shade ferns Figure 2.1.. This classification is not strict as some species are also grow well in opened and light shady areas. D. polypodioides are seen in the gap areas of thick forest and also in the margin forest. There are several species found growing in both light shady and deep shady areas. D. bantamense, D. batuayauense, D. cordifolium , D. crinitum, D. crameri, D. dilatatum, D. donianum, D. fraxinifolium, D. lobbianum, D. loerzingii, D. malaccense, D. melanolepis, D. riparium, and D. sorzogonense can be found in light shady and deep shady areas. 19

2.3.2. Diversity of Diplazium Based on Elevation

Table 2.3.. and Figure 2.2. show the diversity of Diplazium based on elevation. The species number of Diplazium culminate at 1000-1500 m. Amount of 19 species of Diplazium distribute at the elevation. Some studies on diversity across elevation Shmida Wilson 1985; Gentry Dodson 1987; Colwell Hurtt 1994 also reveal that peak diversity occur at intermediate elevations. Lomolino 2001 predicted that species-density should peak at an intermediate elevation and the peak should occur at transition zone between the two species- rich, juxtaposed communities. Because detailed information on climatic gradients, dispersal, population persistent and anthropogenic disturbance are generally unavailable, it is difficult to evaluate critically some of the predictions associated with causal explanation for peaks in diversity at intermediate elevations Lomolino 2001. Some species of Diplazium, such as D. atrosquamosum, D. beamanii, and D. squarrosum, are only occurring at upper elevation zones Table 2.3.. Above 3000 m, there was only found D. moultonii. Some scientists Kikkawa Wlliams 1971; Gentry Dodson 1987; McCoy 1990; Rahbek 1995 reported that speciation and endemicity peak at the intermediate to high elevations. Rahbek 1995 presumed that upper elevation zones may provide the geographical isolation required for speciation. If the montane zones are both isolated and large enough to allow population persistence and divergence over evolutionary time, they may represent hotspots of speciation and endemicity. Some species that presumed to be closely related have different in the range of distribution based on altitude. D. lobbianum and D. bantamense are presumed closely related. The two species share character combination as follow: scales toothed; fronds imparipinnate; pinnae oblong-ovate; vein free, forked, texture chartaceous. Ecologically D. lobbianum is found at 1500-1800 m, whereas D. bantamense usually below 1500 m. 20 Table 2.2. Diversity of Diplazium based on Elevation Elevation m Species 20- 500 D. accedens, D. acuminatum, D. aequibasale, D. angustipinna, D. bantamense, D. batuayauense, D. crenatoserratum, D. crinitum, D. hewittii, D. lomariaceum, D. pallidum, D. petiolare, D. polypodioides, D. porphyrorachys, D. riparium , D. tomentosum, D. wahauense, D. xiphophyllum 500-1000 D. accedens, D. acuminatum, D. bantamense, D.. cordifolium, D. crenatoserratum, D. cumingii, D. hewittii, D. hottae, D. laevipes, D. lomariaceum, D. pallidum, D. petiolare, D. poiense, D. polypodioides, D. simplicivenium, D. sorzogonense, D. tomentosum, D. umbrosum, D. xiphophyllum 1000-1500 D. accedens, D. asymmetricum, D. barbatum, D. cordifolium, D. crenatoserratum, D. cumingii, D. dilatatum, D. halimunense, D. hewittii, D. laevipes, D. lomariaceum, D. latisquamatum, D. moultonii, D. pallidum, D. petiolare, D. poiense, D. polypodioides; D. sorzogonense; D. tomentosum, D. tricholepis, D. umbrosum, D. velutinum, D. xiphophyllum. 1500-2000 D. atrosquamosum, D. barbatum, D. cordifolium, D. fuliginosum, D. latisquamatum, D. lomariaceum, D. moultonii, D. poiense, D. polypodioides, D. sorzogonense, D. speciosum, D. tricholepis, D. umbrosum, D. velutinum 2000-2500 D. atrosquamosum, D. barbatum, D. cordifolium, D. fuliginosum, D. latisquamatum, D. moultonii, D. sorzogonense, D. speciosum, D. tricholepis 2500-3000 D. cordifolium, D. fuliginosum, D. latisquamatum, D. moultonii, D. speciosum 3000-3400 D. moultonii The individuals with different ploidy level in the same species sometimes grow in the different altitude See Chapter 5. Diploid D. pallidum from Java, Borneo, and Sumatra were found at 200 m, 240 m and 30 to 85 m, respectively. Whereas the tetraploid ones were found at 1000 – 13000 m. Some closely related species may occur in overlapped distribution. D. insigne is evidently closely allied to D. accedens Holttum 1940. The two species share in characters: dull brown toothed scales with narrow thickening black strands, the deltoid deeply lobed apex of fronds and copiously goniopterid venation. The first species distributes from 600 m to 1200 m and the second species from 80 m to 1400 m. 21 Figure 2.1. a-b. Light shade-ferns of Diplazium. a. D. hottae; b. D. loerzingii; c-d. Deep shade-ferns. c. D. cordifolium; d. D. tomentosum. 5 10 15 20 25 0-500 501-1000 1001-1500 1501-2000 2001-2500 2501-3000 3000-3500 Elevation Range meter N umber of Spec ies Fig. 2.2. Elevational distribution of Diplazium species in West Malesia 22

2.4. Conclusions

Based on their main habitat, Diplazium can be divided into three major groups: dryland, riparian and rheophytic. Most of species are terrestrial dryland ferns and found at 20 – 3400 m above sea level in the primary and secondary forest on moist humus-rich soil in light and deep shady places 64 species. There are only found five of the riparian species, namely D. aequibasale, D. riparium, D. fuliginosum, D. lomariaceum, and D. porphyrorachis. The rheohytic species are found in D. aequibasale and D. wahauense. The most species number of Diplazium were culminated at 1000-1500 m. The lowest number of species occurred at 2500-3400 m. The individuals with different ploidy level in the same species sometimes grow in the different gradient habitats. 23

CHAPTER 3 THE DISTRIBUTION OF WEST MALESIAN DIPLAZIUM INSIDE AND

OUTSIDE MALESIA 3.1. Introduction The fern genus Diplazium is an important component of tropical rainforest of the Old World and the New World. It is a terrestrial ferns which is commonly found in the moist ground at the humus rich soil both in the primary and secondary forest at 20-3400 m altitude. Most of species grow in shadowed place and fond of moist humus rich soil. Some species are locally abundant by stream in the mountains. Only a few species are found in limestone areas and in rheophitic areas See Chapter 2. Since 1801 Diplazium have been the subject of numerous taxonomic studies conducted, including morphological, anatomical, cytological and molecular investigations. It is estimated that the genus consisting of about 400 species Ching 1964a, Copeland 1947. Roos 1995 estimated that 300 species of its are found in Malesian region. Few species are found in continental Africa Kramer et al 1990. In the Neotropics there are nearly 100 species Pacheco 2004. Distributional data are important in answering many questions about polyploidy and speciation Baack 2004. Usually, increasing in ploidy level is associated with the origin of novel adaptations Levin 2002. Polyploid often occupy different habitats from those of their diploid parents Soltis Soltis 2000. Study of the biogeographical distribution of organisme are also very useful in inferring the monophyly of a taxon. The elementary questions of historical biogeography concern areas of endemism and their relationships Nelson Platnick 1981. By analogy to phylogenic systematics, where species or higher taxa are grouped, in cladistic biogeopgraphy the units grouped are areas of endemism Linder 2001. For example, study on molecular phylogenetic and historical biogeography of Hawaiian Dryopteris Dryopteridaceae Geiger Ranker 2005 indicate that Hawaiian Dryopteris is not monophyletic, and there