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On the discovery of second living population of Adenomus kandianus (Günther, 1872) from Sri Lanka: with the bioecology, and detailed redescription to the species
Abstract and Figures
Adenomus is an endemic genus of toads to Sri Lanka known from three species. Adenomus kandianus had been considered extinct until its recent rediscovery from the Peak Wilderness in 2012, after a lap of 136 years. Here we report the second existing population of Adenomus kandianus from lower part of the Pidurutalagala Forest Reserve, in central Sri Lanka. Detailed descriptions of male and female Adenomus kandianus along with the holotype are provided. Habitats around this forest area up to 1300 m elevation have been replaced rapidly by human encroachments primarily for tea plantations, cultivated lands and human settlements. Lower part of the Pidurutalagala Forest Reserve, which supports high faunal diversity, has long been under studied and requires further exploration.
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... To confirm the species identification of the newly-discovered Adenomus populations (Gabadage et al. 2014), two tiny toe clips from each morphospecies (mature males) were obtained, preserved in absolute ethanol, and stored at -20° C. DNA was extracted using Qiagen tissue-extraction kits, following manufacture protocols. A fragment of ca 600 bp of 16S rRNA was PCR-amplified (Palumbi 1996). ...
... Based on field records from this study and published literature (Gabadage et al. 2014;Karunarathna et al. 2012;Wickramasinghe et al. 2012), seven presence locations from two regions (Table S1) were used to produce the predicted distribution map of Adenomus kandianus using MaxEnt version 3.3.3k (Phillips et al. 2004). ...
... A single thriving population is insufficient to guarantee the survival of this species even through the next few decades; it has been witnessed limited numbers of thriving populations being wiped out within short periods of time (Corn & Fogleman 1984). It remains to be established how the other known populations of these toads are faring, especially the recently discovered population (Gabadage et al. 2014) Improved niche models that take into consideration all known populations of A. kandianus suggest a fairly large area of occupancy (ca. 670 km 2 ) within the Central Hills (Fig. 3). ...
Endemic to Sri Lanka, genus Adenomus contains two torrent-associated toad species whose ecology and natural history in the wild is virtually unknown. Adenomus kelaartii is relatively common, with a wide geographic distribution. Its sister species, A. kandianus , however, is restricted to two isolated populations in fast-disappearing montane and sub-montane forests. Formally declared extinct after not being recorded for over a century, following several years of surveying, a few A. kandianus were found in 2012 and referred to as "the world's rarest toad." However, tadpoles of A. kandianus bearing unique ventral suckers were soon discovered, but the rarity of the adult and the profusion of tadpoles were never explained. Here, using ecological methods, niche modeling and DNA-barcoding, we aim to understand the ecology, natural history and distribution of this rare toad. Following a two-year study of occurrence, habits and habitat associations of adults and larvae, we show this to be a secretive species with a patchy distribution. During non-mating periods female toads ( N = 23) were found in primary forests habitat up to 650 m away from the breeding streams, and predominantly males in the riparian zone (12 males, 2 females). Following heavy rain they form large ( N = 388) but patchy mating congregations in torrential streams (six sites; range 0−95 mating pairs; mean = 25, SD = 38.16, CV = 152%). Amplexed pairs swim synchronously, enabling them to traverse fast currents. Egg-laying sites remain unknown, but ability to dive, vocalize underwater, and characteristics of the eggs, suggests that they lay eggs in dark recesses of the stream. Quadrat sampling of tadpoles show microhabitat partitioning (in depth, flow-rate and substrate conditions) within the stream: the greatest diversity of larval developmental stages (25-42) in slow-flowing (depth, 0.75−1.5 m) rocky areas; more robust stages (31−39) bearing sucker discs utilise rocky-rapids (depth, 0.25−0.75 m); metamorphic stages (43-45) use stream margins (depth, <0.25 m); slow flowing silt covered areas of the stream were unoccupied, irrespective of the depth. DNA barcoding of the 16S rRNA gene fragment from the two known localities confirms the identity of the Pedro population also as A. kandianus . The uncorrected pairwise genetic distance of 0.1−0.7% suggests historical gene flow between the two populations. Distribution modeling (using MaxEnt), with forest-cover layers added, predicts a very small remaining area of suitable habitats (an area of occupancy of 16 km ² and an extent of occurrence of 128 km ² ) isolated by habitats that are not conducive to these toads. While the healthy population recorded at one site gives hope for the survival of the species, long-term conservation of this climatically and ecologically restricted species hinges largely on the preservation of cloud and riparian forests and the unpolluted high-flow torrents.
... To confirm the species identification of the newly-discovered Adenomus populations (Gabadage et al. 2014), two tiny toe clips from each morphospecies (mature males) were obtained, preserved in absolute ethanol, and stored at -20° C. DNA was extracted using Qiagen tissue-extraction kits, following manufacture protocols. A fragment of ca 600 bp of 16S rRNA was PCR-amplified (Palumbi 1996). ...
... Based on field records from this study and published literature (Gabadage et al. 2014;Karunarathna et al. 2012;Wickramasinghe et al. 2012), seven presence locations from two regions (Table S1) were used to produce the predicted distribution map of Adenomus kandianus using MaxEnt version 3.3.3k (Phillips et al. 2004). ...
... A single thriving population is insufficient to guarantee the survival of this species even through the next few decades; it has been witnessed limited numbers of thriving populations being wiped out within short periods of time (Corn & Fogleman 1984). It remains to be established how the other known populations of these toads are faring, especially the recently discovered population (Gabadage et al. 2014) Improved niche models that take into consideration all known populations of A. kandianus suggest a fairly large area of occupancy (ca. 670 km 2 ) within the Central Hills (Fig. 3). ...
Endemic to Sri Lanka, genus Adenomus contains two torrent-associated toad species whose ecology and natural history in the wild is virtually unknown. Adenomus kelaartii is relatively common, with a wide geographic distribution. Its sister species, A. kandianus, however, is restricted to two isolated populations in fast-disappearing montane and sub-montane forests. Formally declared extinct after not being recorded for over a century, following several years of surveying, a few A. kandianus were found in 2012 and referred to as "the world's rarest toad." However, tadpoles of A. kandianus bearing unique ventral suckers were soon discovered, but the rarity of the adult and the profusion of tadpoles were never explained. Here, using ecological methods, niche modeling and DNA-barcoding, we aim to understand the ecology, natural history and distribution of this rare toad. Following a two-year study of occurrence, habits and habitat associations of adults and larvae, we show this to be a secretive species with a patchy distribution. During non-mating periods female toads (N = 23) were found in primary forests habitat up to 650 m away from the breeding streams, and predominantly males in the riparian zone (12 males, 2 females). Following heavy rain they form large (N = 388) but patchy mating congregations in torrential streams (six sites; range 0−95 mating pairs; mean = 25, SD = 38.16, CV = 152%). Amplexed pairs swim synchronously, enabling them to traverse fast currents. Egg-laying sites remain unknown, but ability to dive, vocalize underwater, and characteristics of the eggs, suggests that they lay eggs in dark recesses of the stream. Quadrat sampling of tadpoles show microhabitat partitioning (in depth, flow-rate and substrate conditions) within the stream: the greatest diversity of larval developmental stages (25-42) in slow-flowing (depth, 0.75−1.5 m) rocky areas; more robust stages (31−39) bearing sucker discs utilize rocky-rapids (depth, 0.25−0.75 m); metamorphic stages (43-45) use stream margins (depth, <0.25 m); slow flowing silt covered areas of the stream were unoccupied, irrespective of the depth. DNA barcoding of the 16S rRNA gene fragment from the two known localities confirms the identity of the Pedro population also as A. kandianus. The uncorrected pairwise genetic distance of 0.1−0.7% suggests historical gene flow between the two populations. Distribution modeling (using MaxEnt), with forest-cover layers added, predicts a very small remaining area of suitable habitats (an area of occupancy of 16 km2 and an extent of occurrence of 128 km2) isolated by habitats that are not conducive to these toads. While the healthy population recorded at one site gives hope for the survival of the species, long-term conservation of this climatically and ecologically restricted species hinges largely on the preservation of cloud and riparian forests and the unpolluted high-flow torrents.
... Adenomus kandianus Günther, 1872;Manamendra-Arachchi & Pethiyagoda, 1998;Gabadage et al., 2014Günther, 1872Manamendra-Arachchi & Pethiyagoda, 1998;Gabadage et al., 2014; Altiphrynoides malcolmi ---- Altiphrynoides osgoodi Loveridge, 1932 Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus balios Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus barbotini Lescure & Marty, 2000----Lötters et al., 2011Atelopus boulengeri McDiarmid, 1971McDiarmid, 1971McDiarmid, 1971 Atelopus carbonerensis Rivero, 1974Coloma, 1997Coloma, 1997 Atelopus carrikeri Ruthven, 1916;McDiarmid, 1971;Ruiz-Carranza et al., 1994McDiarmid, 1971Ruiz-Carranza et al., 1994McDiarmid, 1971Ruiz-Carranza et al., 1994;Atelopus certus McDiarmid, 1971McDiarmid, 1971 McDiarmid, 1971 Atelopus chirripoensis Miyata, 1980;Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus cruciger McDiarmid, 1971;Lötters et al., 2004 MOP pers. obs.;McDiarmid, 1971;Lötters et al., 2004 MOP pers. ...
... Adenomus kandianus Günther, 1872;Manamendra-Arachchi & Pethiyagoda, 1998;Gabadage et al., 2014Günther, 1872Manamendra-Arachchi & Pethiyagoda, 1998;Gabadage et al., 2014; Altiphrynoides malcolmi ---- Altiphrynoides osgoodi Loveridge, 1932 Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus balios Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus barbotini Lescure & Marty, 2000----Lötters et al., 2011Atelopus boulengeri McDiarmid, 1971McDiarmid, 1971McDiarmid, 1971 Atelopus carbonerensis Rivero, 1974Coloma, 1997Coloma, 1997 Atelopus carrikeri Ruthven, 1916;McDiarmid, 1971;Ruiz-Carranza et al., 1994McDiarmid, 1971Ruiz-Carranza et al., 1994McDiarmid, 1971Ruiz-Carranza et al., 1994;Atelopus certus McDiarmid, 1971McDiarmid, 1971 McDiarmid, 1971 Atelopus chirripoensis Miyata, 1980;Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus cruciger McDiarmid, 1971;Lötters et al., 2004 MOP pers. obs.;McDiarmid, 1971;Lötters et al., 2004 MOP pers. ...
... Adenomus kandianus Günther, 1872;Manamendra-Arachchi & Pethiyagoda, 1998;Gabadage et al., 2014Günther, 1872Manamendra-Arachchi & Pethiyagoda, 1998;Gabadage et al., 2014; Altiphrynoides malcolmi ---- Altiphrynoides osgoodi Loveridge, 1932 Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus balios Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus barbotini Lescure & Marty, 2000----Lötters et al., 2011Atelopus boulengeri McDiarmid, 1971McDiarmid, 1971McDiarmid, 1971 Atelopus carbonerensis Rivero, 1974Coloma, 1997Coloma, 1997 Atelopus carrikeri Ruthven, 1916;McDiarmid, 1971;Ruiz-Carranza et al., 1994McDiarmid, 1971Ruiz-Carranza et al., 1994McDiarmid, 1971Ruiz-Carranza et al., 1994;Atelopus certus McDiarmid, 1971McDiarmid, 1971 McDiarmid, 1971 Atelopus chirripoensis Savage & Bolaños, 2009Savage & Bolaños, 2009 ----Atelopus chrysocorallus --------Atelopus coynei Miyata, 1980;Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus cruciger McDiarmid, 1971;Lötters et al., 2004 MOP pers. obs.;McDiarmid, 1971;Lötters et al., 2004 MOP pers. ...
... Adenomus kandianus Günther, 1872;Manamendra-Arachchi & Pethiyagoda, 1998;Gabadage et al., 2014Günther, 1872Manamendra-Arachchi & Pethiyagoda, 1998;Gabadage et al., 2014; Altiphrynoides malcolmi ---- Altiphrynoides osgoodi Loveridge, 1932 Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus balios Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus barbotini Lescure & Marty, 2000----Lötters et al., 2011Atelopus boulengeri McDiarmid, 1971McDiarmid, 1971McDiarmid, 1971 Atelopus carbonerensis Rivero, 1974Coloma, 1997Coloma, 1997 Atelopus carrikeri Ruthven, 1916;McDiarmid, 1971;Ruiz-Carranza et al., 1994McDiarmid, 1971Ruiz-Carranza et al., 1994McDiarmid, 1971Ruiz-Carranza et al., 1994;Atelopus certus McDiarmid, 1971McDiarmid, 1971 McDiarmid, 1971 Atelopus chirripoensis Savage & Bolaños, 2009Savage & Bolaños, 2009 ----Atelopus chrysocorallus --------Atelopus coynei Miyata, 1980;Coloma, 1997Coloma, 1997Coloma, 1997 Atelopus cruciger McDiarmid, 1971;Lötters et al., 2004 MOP pers. obs.;McDiarmid, 1971;Lötters et al., 2004 MOP pers. ...
Most anurans possess a tympanic middle ear (TME) that transmits sound waves to the inner ear; however, numerous species lack some or all TME components. To understand the evolution of these structures, we undertook a comprehensive assessment of their occurrence across anurans and performed ancestral character state reconstructions. Our analysis indicates that the TME was completely lost at least 38 independent times in Anura. The inferred evolutionary history of the TME is exceptionally complex in true toads (Bufonidae), where it was lost in the most recent common ancestor, preceding a radiation of >150 earless species. Following that initial loss, independent regains of some or all TME structures were inferred within two minor clades and in a radiation of >400 species. The reappearance of the TME in the latter clade was followed by at least 10 losses of the entire TME. The many losses and gains of the TME in anurans is unparalleled among tetrapods. Our results show that anurans, and especially bufonid toads, are an excellent model to study the behavioural correlates of earlessness, extratympanic sound pathways, and the genetic and developmental mechanisms that underlie the morphogenesis of TME structures.
... A major drawback in conservation of Sri Lanka's herpetofauna is the lack of spatially explicit records on species taxonomy and biogeography (Gabadage et al., 2014). This study intends to provide a compilation of records from this less-studied area, to support future surveys, and conservation and management decisions within the region. ...
Jaffna peninsula is quite an unexplored area of Sri Lanka's lowland dry zone. We constructed a species checklist for all herpetofauna of this area based on a short-term field survey, a comprehensive literature review, museum specimens, and observations made by field herpetologists. Based on 200 × 10 m belt transects, we surveyed herpetofauna both during day and night time, in 10 different types of habitats. The species checklist we compiled comprised 44 species of reptiles (including three nationally threatened, one globally threatened, and eight endemic species) and 15 species of amphibians (including one nationally threatened and three endemic species). Based on published literature, museum specimens, expert opinions, and current field survey, we documented 85 species of herpetofauna in this area. Of this entire list, we were unable to record the presence of 25 species through our field survey. Our field survey documented 18 species that were not previously reported from Jaffna Peninsula. Our study revealed that inland water bodies, cultivated lands, home gardens, and coastal beaches are of high importance for native herpetofauna of Jaffna peninsula. Many human disturbances, such as habitat alterations, vengeful killing, consumption overexploitation, and road mortality are the key threats encountered by herpetofauna in Jaffna. Our intention of this study is to compile baseline information on diversity of amphibians and reptiles to support more detailed studies in future and assist conservation and management decisions within the region. We believe that our study will provide a basic foundation for conservation planning and future research.
... Recent research has rediscovered a few species of amphibians that were considered extinct. Gabadage et al. (2014) emphasized that further extensive surveys in the central highlands of Sri Lanka are essential to reveal species that are currently considered TAPROBANICA VOL. 07: NO. 04 extinct. ...
During the present survey, 11 species of amphibians and 10 species of reptiles were recorded (Appendix 1). Interestingly, a critically endangered species Pseudophilautus microtympanum and six endangered amphibian species were recorded. Duttaphrynus melanostictus was the most common amphibian species observed and was the only one found in all six habitats. This was followed by P. alto and Hylarana temporalis. During this study, 10 species of reptiles including 6 endemic species were observed. Among them, two critically endangered species (Cnemaspis cf. clivicola and Lankascincus cf. sripadensis) and four endangered species were recorded. A lizard Calotes calotes was the most common reptile species in Lippakelle estate followed by Eutropis carinata and Rhinophis blythii.
The tropical island nation of Sri Lanka is a biodiversity hotspot with a high diversity and endemism of amphibians. The endemic, stream-dwelling Kandian torrent toad Adenomus kandianus is Critically Endangered and was considered to be extinct until its rediscovery in 2012. The species is now known from two localities in tropical montane forests. We conducted a 4-year study using transect surveys and opportunistic excursions to assess habitat associations, demographics and abundance of A. kandianus in and around Pidurutalagala Conservation Forest. We recorded a mean of 44.25 post-metamorphs per year, with a density of < 1 individual per 100 m ² , with occurrence within a narrow extent (c. 0.005 km ² ) of the stream channel. Behaviour and microhabitat selection varied depending on sex and stage of maturity. The species preferred moderately sized montane streams with rocky substrates and woody debris, colder temperatures, and closed-canopy, intact riparian forests. We noted size-based reversed sexual dimorphism and a strong ontogenetic relationship between snout–vent length and body weight. Anthropogenic activities such as intensive crop farming deterred the species; proximity to croplands had a negative influence on abundance. We recommend re-delineation of the boundary of Pidurutalagala Conservation Forest to incorporate the toad's habitat into the core of the reserve and thus limit the impacts of human activities. Conservation and management actions such as ex-situ breeding, population monitoring, and restoration of degraded habitats could also contribute towards the persistence of this toad. Our findings provide useful insights into ecological research on and conservation of range-restricted aquatic amphibians.
Eight new species of Pseudophilautus (Pseudophilautus bambaradeniyai, P. dayawansai, P. jagathgunawardanai, P. karunarathnai, P. newtonjayawardanei, P. puranappu, P. samarakoon, and P. sirilwijesundarai) were discovered as a result of a survey carried out to study the herpetofaunal diversity with the changes in elevation in the Sripada World Heritage Site (Peak Wilderness), Central Hills of Sri Lanka. Detailed descriptions of new species along with colour photographs and line drawings for each species are provided herein. The new species possess unique morphological characters and are well distinguishable from one another that could be easily identified in the field. The conservation status of all species described here, have been considered Critically Endangered, except for P. newtonjayawardanei, as all the new species are recorded from single locations, and their habitats are under severe threat.
Adenomus kandianus Günther (1872) was previously known only from two specimens both deposited in the British Museum, the holotype BMNH1947.2.20.63, and the syntype of A. kelaarti BMNH1947.2.20.62. The only record of A. kandianus since the initial description in 1872 was by Ferguson in 1876, who mentions two specimens resembling Bufo kandianus in his collection, making A. kandianus the world's rarest toad. The species had not been reported since, and was considered extinct. Here we report on its rediscovery.
Pseudophilautus hypomelas (Günther, 1876), was previously known from the type collection of 14 specimens deposited in the Natural History Museum, London. There has been no record of this species since the original description by Günther in 1876, and subsequently this species was considered extinct. In recent explorations however, the species has been rediscovered from the Peak Wilderness, Central Hills of Sri Lanka, with a rediscription of the species from fresh collections.
Sympatric populations of the leaf-frogs Phyllomedusa distincta (2n = 26) and P. tetraploidea (4n = 52) were studied in southeastern Brazil. In a region of sympatry, seven of 15 leaf-frogs were triploid hybrids (3n = 39). The advertisement calls of both species are similar, and may not function adequately as a premating isolation mechanism. Triploids apparently exhibit low fertility or sterility, supporting the assertion that diploid and tetraploid populations are valid species. We suggest that P. tetraploidea originated by autopolyploidy of P. distincta, based on the following evidence: (1) the indistinguishable vocalizations of diploid and tetraploid species, and (2) the geographic distribution of species in the Phyllomedusa burmeisteri group.
There are three species of Adenomus (Adenomus dasi ; A. kandianus and A. kelaartii) in Sri Lanka and all of them are endemic (endemic relict genus), while A. kandianus is Extinct. According to the published literature, A. dasi is known only from a handful of specimens collected from a small stream with rocky habitat near Moray Estate in Samanala Nature Reserve (>1300m), Mousakelle in the wet zone. This species
is identifed as a Critically Endangered species in Sri Lanka due to its restricted range and also globally as a Data Defcient species due to lack of required information about its biology and ecology.
Mating decisions contribute to both the fitness of individuals and the emergence of evolutionary diversity, yet little is known about their cognitive architecture. We propose a simple model that describes how preferences are translated into decisions and how seemingly disparate patterns of preference can emerge from a single perceptual process. The model proposes that females use error‐prone estimates of attractiveness to select mates based on a simple decision rule: choose the most attractive available male that exceeds some minimal criterion. We test the model in the túngara frog, a well‐characterized species with an apparent dissociation between mechanisms of mate choice and species recognition. As suggested by our model results, we find that a mate attraction feature alters assessments of species status. Next, we compare female preferences in one‐choice and two‐choice tests, contexts thought to emphasize species recognition and mate choice, respectively. To do so, we use the model to generate maximum‐likelihood estimators of preference strengths from empirical data. We find that a single representation of preferences is sufficient to explain response probabilities in both contexts across a wide range of stimuli. In this species, mate choice and species recognition are accurately and simply summarized by our model. While the findings resolve long‐standing anomalies, they also illustrate how models of choice can bridge theoretical and empirical treatments of animal decisions. The data demonstrate a remarkable congruity of perceptual processes across contexts, tasks, and taxa.
While Pidurutalagala is a gneiss complex of Precambrian origin and situated 7° north of the equator, Pangrango-Gede are twin volcanoes, almost 7° south. Altitudes and climate are similar (monsoons, high precipitation, mist above 1,500 m, and frost occurrence). Both islands were governed partly or entirely by European powers during the last century and have well-known botanical gardens. The floras are related, though many genera are lacking in Ceylon. This is due to the cul-de-sac location of Ceylon in contrast to Java which constitutes a bridge between Asia and Australia. The zonation of vegetation is somewhat different: montane rainforest with high trees extends to 2,000 m in Java, while in Ceylon the lower montane forest (hill-dipterocarps) ends at 1,500 m a.s.l. Above 2,000 m and 1,500 m, respectively, mossy forest covers the slopes. The fauna of both mountains has many similarities; big herbivores were once represented by the elephant in Ceylon and rhinoceros in Java. The forests around Pidurutalagala are not protected, while those of Pangrango-Gede are conserved in a national park. /// Le Pidurutalagala est un massif de gneiss d'origine précambrienne situé à 7° au nord de l'équateur, alors que le Pangrango-Gede est constitué de deux volcans jumeaux situés à 7° au sud de celui-ci. L'altitude et le climat sont similaires (moussons, précipitations abondantes, brouillard au-dessus de 1.500 m et gelée). Ces deux îles furent partiellement ou totalement gouvernées par les puissances européennes au cours du siècle dernier, et possèdent des jardins botaniques réputés. Les flores sont voisines bien que quelques genres n'existent pas à Ceylan, à cause de la position en cul-de-sac de Ceylan par rapport à Java qui forme un pont entre l'Asie et l'Australie. La zonation végétale est tant soit peu différente: la forêt humide à grands arbres de l'étage montagnard atteint 2.000 m à Java, alors qu'à Ceylan la forêt de l'étage montagnard inférieur (genre dipterocarpus) se termine à 1.500 m au-dessus du niveau de la mer. Au-dessus de 2.000 m et 1.500 m respectivement, les pentes sont couvertes de forêts moussues. Les faunes de ces deux montagnes présentent de nombreuses similarités: les grands herbivores étaient à une époque représentés par l'éléphant à Ceylan et le rhinoceros à Java. Les forêts du Pidurutalagala ne sont pas protégées par le gouvernement, alors que celles du Pangrango-Gede le sont en tant que parc national. /// Pidurutalagala ist ein Massiv aus präkambrischen Gneisen und liegt 7° nördlich des Äquators, während Pangrango-Gede, 2 zusammenhängende Vulkankegel, fast 7° südlich des Äquators aufragen. Höhe und Klima sind ähnlich (Monsune, hohe Niederschläge, häufige Nebel oberhalb 1500 m und gelegentliche Nachtfröste). Beide Inseln blicken auf eine koloniale Vergangenheit zurück und beherbergen berühmte botanische Gärten gleichen Alters. Die Floren sind verwandt, obwohl viele Genera auf Ceylon fehlen (z.B. alle Coniferen und Fagaceen). Diese Tatsache ergibt sich aus der isolierten Lage Ceylons im Gegensatz zu Java, das eine Brücke zwischen Asien und Australien ist. Die Zonierung der Vegetation ist etwas unterschiedlich: Hoher Bergregenwald reicht am Pangrango-Gede bis 2000 m - in Ceylon nur bis 1500 m. Oberhalb schließt jeweils niedriger und moosreicher Nebelwald an. Die Fauna beider Berge weist viele Ähnlichkeiten auf. Früher durchzogen Elefanten die Wälder des Pidurutalagala und Java-Nashörner die des Pangrango-Gede. Die Wälder am Pidurutalagala sind nicht als Schutzgebiet ausgewiesen, während die am Pangrango-Gede den Status eines Nationalparks genießen.
With Sri Lanka's old-growth forests having been reduced to less than 20% of their pre-colonial extent, increasing areas of land, formerly heavily influenced by humans, are being allowed to return to secondary forests. These range from land recovering from swidden cultivation in the dry zone, through abandoned tea plantations in the lower-montane zone, to partly-logged forests throughout the country. Although the secondary vegetation of these ‗emerging ecosystems' is often dominated by alien plant species and in-cludes only a depauperate native flora, many threatened animals, ranging from amphibians to elephants, are able to utilize them for part or all of their life cycles. These novel ecosystems offer valuable conserva-tion opportunities in two ways: (1) by increasing the area of occupancy of threatened species they contrib-ute directly to a reduction in the level of threat; and (2) they provide a filter for triage, whereby threatened species that are intolerant of modified habitats could be awarded higher priority in the design of recovery plans. Available data suggest that among the Sri Lankan terrestrial vertebrates presently assessed as Endangered or Critically Endangered in the IUCN Red List, 12 of 14 mammal species, three of four reptile species and 40 of 48 amphibian species occur also in emerging ecosystems. Despite their impoverished plant diversity, therefore, such ecosystems should be viewed as a conservation opportunity rather than a threat; they should be incorporated into the national protected areas network and their biodiversity monitored, especially in relation to threatened species.Those that establish stable populations over multiple generations could be down-listed so that greater conservation attention could be allocated to threatened species obligatorily dependent on old-growth forests.