Western Ghats-Sri Lanka Biodiversity Hotspot Research Articles

Niche model based conservation and ecorestoration area prediction of threatened Prioria pinnata (Fabaceae) and conservation implication on IUCN status

Prioria pinnata (Roxb. ex DC.) Breteler, a threatened endemic canopy tree in the Western Ghats-Sri Lanka biodiversity hotspot, which is threatened by habitat loss and low density. Bioclimatic modelling predicts 2999 km2 of potential habitat across nine ecoregions, but 2452 km2 is converted for agriculture, making it unsuitable for niche-specific species restoration. Combining Grinnellian and Eltonian niche factors enhances model accuracy and predictions using a modified Niche modelling coupled with community composition. The study adds more information to the IUCN Red List assessment, expanding the Extent of Occurrence and Area of Occupancy. The species' status has been upgraded from Endangered to Vulnerable due to recovery and increased awareness. A niche profile-based management plan and seedling reintroduction are recommended for this threatened endemic canopy tree.

Status of crop plants of agricultural importance in Kerala state, India: an update

The state of Kerala in India, a part of the Western Ghats–Sri Lanka biodiversity hotspot, is blessed with rich biodiversity including agrobiodiversity. Richness in crop diversity is attributed to the wide topographic and climatic niches, long history of outside contacts, personal craving for experimenting new crops, practice of high-density multi-species cropping system, etc. Evidence from several field exploration trips, herbarium survey, reliable literature and other sources has revealed that 306 crop taxa (excluding medicinal and aromatic plants, ornamentals and forestry species) belonging to 290 species coming under 179 genera and 61 families, are being cultivated in different areas of this state. This includes crops belonging to crop-groups—cereals and millets (11), pseudocereals (2), pulses (7), oilseeds (7), fibres (3), forages (14), fruits and nuts (107), vegetables (86; 18-being tuber crops), spices and condiments (20), plantation crops (10) and others (29). Of 306 taxa, 63 occur in the wild state as well; 43 are of only recent cultivation (< 15 years) or under trial cultivation by innovative farmers; and 43 are confined only in (sub)temperate hills. This is more than double (104% increase) the earlier estimate of crops made during 2011, which also included species of medicinal/aromatic/ornamental value (5), not under cultivation in Kerala (3), mistaken identity (3) and synonym (1). We provide here user-friendly crop-group wise categorization of taxa with their vernacular names for easy cross reference. This communication also discusses about the issue of botanical misidentification of crop plants, species of doubtful cultivation status, specialty crops, potential exotic crops, etc.

The role of sea-level and climate changes in the assembly of Sri Lankan biodiversity: A perspective from the Miocene Jaffna Limestone

As part of the Western Ghats-Sri Lanka biodiversity hotspot, Sri Lanka harbors a rich and diverse fauna with a considerable number of endemic species, especially in the wet southwestern part of the island. Understanding the origin of this biodiversity requires consideration of the land bridge history between the island and southern Peninsular India. To examine the influence of fluctuating sea levels and climate on island connectivity and isolation during the Miocene, we describe the lithological succession of the Jaffna Limestone in surface outcrops of north(west)ern Sri Lanka and interpret it with respect to palaeoenvironments and sequence stratigraphy. A stack of three marine intervals was identified, which were deposited in seagrass-, coral reef-, and nearshore siliciclastic environments of a land-attached carbonate platform and are separated by caliche and palaeokarst unconformities. They represent high sea-level peaks during the long-term sea-level maximum related to the Middle Miocene Climate Optimum (MMCO). In support of divergence time from Sri Lankan and south Indian species, it is argued that the Palk Isthmus connected Sri Lanka to mainland India prior the MMCO (~17–15 Ma) and after the Middle Miocene Climate Transition (~15–13 Ma), whereas a marine barrier continued to persist during low sea-level stands associated with the Mi2, Mi3a and Mi3 glaciations within this period of time. The early and middle Miocene landbridge connections opened up dispersal opportunities for terrestrial animals. Species migrations via the Palk Isthmus were, however, impacted by a climatic filter, which promoted a high level of ancient endemism on Sri Lanka. Our results indicate that the Sri Lankan sub-center of biodiversity started to evolve in response to increased sea-level and climate variability associated with Antarctic ice dynamics and the initiation of the South Asian monsoon system during the early stage of the current ice house period.

Drivers of bird beta diversity in the Western Ghats-Sri Lanka biodiversity hotspot are scale dependent: roles of land use, climate, and distance.

In the last 50years, intensive agriculture has replaced large tracts of rainforests. Such changes in land use are driving niche-based ecological processes that determine local community assembly. However, little is known about the relative importance of these anthropogenic niche-based processes, in comparison to climatic niche-based processes and spatial processes such as dispersal limitation. In this study, we use a variation partitioning approach to determine the relative importance of land-use change (ranked value of forest loss), climatic variation (temperature and precipitation), and distance between transects, on bird beta diversity at two different spatial scales within the Western Ghats-Sri Lanka biodiversity hotspot. Our results show that the drivers of local community assembly are scale dependent. At the larger spatial scale, distance was more important than climate and land use for bird species composition, suggesting that dispersal limitation over the Palk Strait, which separates the Western Ghats and Sri Lanka, is the main driver of local community assembly. At the smaller scale, climate was more important than land use, suggesting the importance of climatic niches. Therefore, to conserve all species in a biodiversity hotspot, it is important to consider geographic barriers and climatic variation along with land-use change.

Evolution of Sri Lanka’s Giant Danios (Teleostei: Cyprinidae: Devario): Teasing apart species in a recent diversification

The small, colourful freshwater fishes of the cyprinid genus Devario are among the many vertebrate groups that appear to have diversified on Sri Lanka, a continental Indian Ocean island, which is part of the Western Ghats-Sri Lanka Biodiversity Hotspot. Despite Sri Lanka having been connected with India via a wide isthmus intermittently until the Plio-Pleistocene and almost continuously since then, during sea-level low-stands, the number of species of Devario on Sri Lanka is comparable with that on the Indian Peninsula, some 25 times its size. Here, from a sampling of 27 Devario populations across Sri Lanka’s major river basins and climatic zones, we present and analyze a phylogeny based on mitochondrial and nuclear DNA data. We show that five species of Devario occur on the island, all but one of which are endemic: Devario malabaricus is widespread throughout the lowlands and parts of central hills of Sri Lanka and southern India. A new narrow-range endemic, here described as D. memorialis sp. nov., was discovered in a remnant rainforest habitat at Aranayake (Ma Oya basin) in this study. It is immediately distinguished from Sri Lankan congeners by having only 8 (vs 9–12) branched dorsal-fin rays and by uncorrected pairwise genetic distances of more than 4.0% and 7.8% for cytochrome c oxidase subunit 1 and cytochrome b, respectively. Our results provide strong support for the monophyly of the entire Sri Lankan diversification of Devario. Divergence-timing analysis suggests the common ancestor dispersed to the island in the late Miocene, with the insular diversification in the island’s south-western wet zone taking place during the Plio-pleistocene. There are signs of gene flow between the Indian and Sri Lankan populations of D. malabaricus until the late Pleistocene. Phylogenetic and haplotype-network analyses suggest basin-centric phylogeographic structure within the endemic species; D. malabaricus, however, shows little such structure in the island. Molecular and morphological analyses failed to identify D. annnataliae and D. udenii confidently as distinct species: they are considered synonyms of D. micronema. The morphological variation observed within D. micronema is likely attributable to polymorphism. The discordance between the mitochondrial and nuclear phylogenies for some samples of Devario in the present study suggest signs of mitochondrial introgression.

The pholcid spiders of Sri Lanka (Araneae: Pholcidae).

As part of the Western Ghats-Sri Lanka biodiversity hotspot, Sri Lanka harbors a rich and diverse fauna, especially in the perhumid southwestern part of the island. However, many invertebrate groups such as spiders continue to be poorly studied. The present paper reviews our knowledge about Pholcidae, a family of spiders that is well represented in Sri Lanka, both by numerous (10) introduced species and by a rich native fauna in five genera (described native Sri Lankan species in parentheses): Belisana Thorell, 1898 (6), Leptopholcus Simon, 1893 (1), Pholcus Walckenaer, 1805 (4), Tissahamia Huber, 2018 (4), and Wanniyala Huber Benjamin, 2005 (9). Fourteen species are newly described: Belisana minneriya sp. n., B. badulla sp. n., B. gowindahela sp. n.; Pholcus metta sp. n., P. puranappui sp. n., P. uva sp. n.; Tissahamia karuna sp. n.; Wanniyala mudita sp. n., W. orientalis sp. n., W. upekkha sp. n., W. ohiya sp. n., W. viharekele sp. n., W. mapalena sp. n., and W. labugama sp. n.. All new species are described from males and females. New Sri Lankan records are given for 16 previously described species. Distribution data suggest that most or all of the 24 native species might be endemic to Sri Lanka, but the Indian pholcid fauna remains almost entirely unknown.

An update on the distribution pattern and endemicity of three lesser-known tree species in the Western Ghats, India

The present communication reports an update on the distribution of three endemic tree species of the Western Ghats-Sri Lanka biodiversity hotspot, namely, Atuna indica (Bedd.) Kosterm., Paracroton integrifolius (Airy Shaw) N.P.Balakr. &amp; Chakrab. and Phaeanthus malabaricus Bedd. The discovery of these taxa in the Makutta Ghat of Kodagu District results in the extension of their northern range limits and further enriches the flora of Karnataka state by three more tree species. Within the Western Ghats, these taxa were previously recorded only from the states of Kerala and Tamil Nadu, while Paracroton integrifolius (Airy Shaw) N.P.Balakr. &amp; Chakrab. has also been recorded from Sri Lanka. Nomenclature updates, detailed descriptions, conservation status and relevant notes on the habitat, phenology and distribution localization are supplied. Additionally, field photographs and scanned herbarium specimens are provided to facilitate easy identification of these taxa in the field.

Morphology, ecology, and behaviour of Hylarana intermedia , a Western Ghats frog

Despite being common in the Western Ghats-Sri Lanka biodiversity hotspot, Golden-backed frogs ( Hylarana , Ranidae) remain poorly studied. In this paper, we present some preliminary data on the morphology, behaviour, and habitat use of Hylarana intermedia , a member of the Hylarana aurantiaca species group. We find evidence for female biased size dimorphism, as well as potential shape differences between the sexes in this species. Additionally, we investigate the relationships between traits that may contribute to male conspicuousness (call rates, dorsal coloration, and body size) in two breeding habitats, a paddy field and a trench. Our results suggest both size-dependent and environment-dependent variation in call rate and colour in this species. Specifically, we find evidence against the adoption of sneaker mating strategies by small males in H. intermedia , and instead find variation both within and between populations in traits contributing to male conspicuousness. We conclude by proposing future directions for research on this common frog species.

Cnemaspis rammalensis sp. nov., Sri Lanka's largest day-gecko(Sauria: Gekkonidae: Cnemaspis) from Rammalakanda Man and Biosphere Reserve in southern Sri Lanka.

A new species of rock dwelling gecko belonging to the genus Cnemaspis is described from Sri Lanka based on a suite of morphological features. The species is the largest of its genus described from Sri Lanka so far (snout-vent length 52-54 mm) and is the second largest of the Western Ghats-Sri Lanka Biodiversity Hotspot. It may be diagnosed in details of both scalation (ventrals186-207; mid-subcaudals large; absence of precloacal pores; 15 femoral pores on each side; 22-23 and 23-25 subdigital lamellae on finger IV and on toe IV, respectively; smooth scales on tail dorsum) and colouration (five prominent trilobate shaped cream markings pointing towards head and extending from neck to vent).The species is found in a unique habitat in the Rammalakanda Forest, where it is threatened by deforestation.

DNA barcoding, phylogeny and systematics of Golden-backed frogs (Hylarana, Ranidae) of the Western Ghats-Sri Lanka biodiversity hotspot, with the description of seven new species

A systematic revision of the genus Hylarana in the Western Ghats-Sri Lanka biodiversity hotspot is presented. Species delineation in Hylarana is complicated due to a lack of distinct colour differences or striking morphological characters, leading to potential misidentification. We conducted extensive surveys throughout the Western Ghats-Sri Lanka biodiversity hotspot and performed multiple gene (16S, COI and Cytb) barcoding using 103 samples collected from cultivated land and natural habitats. Genetic distance comparisons and Neighbor Joining trees indicated the presence of at least 14 candidate species in the region, supported by taxa groupings for all three genetic markers. Utilising a combination of molecular and morphological data, we describe seven new species, doubling the number of Hylarana species previously known from this region. We further demonstrate that H. temporalis, which was originally described from Sri Lanka, was misidentified with the Western Ghats endemic species for nearly 100 years. Conversely, H. aurantiaca was originally described from the Western Ghats and misidentified in Sri Lanka. Our study confirms that the distribution of H. temporalis is restricted to Sri Lanka, while H. aurantiaca is endemic to the Western Ghats, and that there are no shared Hylarana species between the two regions. Hylarana flavescens, H. intermedius and H. montanus, previously considered synonyms of H. temporalis are confirmed as valid species. Hylarana bhagmandlensis is removed from the synonymy of H. aurantiaca and placed as a junior subjective synonym of H. montanus. To establish nomenclatural stability, H. flavescens, H. malabarica and H. temporalis are lectotypified and H. intermedius is neotypified. Detailed descriptions, diagnosis, morphological and genetic comparisons, illustrations and data on distribution and natural history are provided for all species. Phylogenetic analyses based on three mitochondrial markers (16S, COI and Cytb) and a fragment of the nuclear Rag1 gene, show complete endemism of the Western Ghats-Sri Lankan species. Four major groups in this region are identified as: 1 — the Hylarana aurantiaca group, endemic to the Western Ghats; 2 — the Hylarana flavescens group, endemic to the Western Ghats; 3 — the Hylarana temporalis group, endemic to Sri Lanka; and 4 — the Hylarana malabarica group from Sri Lanka and India. The discovery of numerous morphologically cryptic Hylarana species in this region further emphasizes the benefits of utilizing an integrative taxonomic approach for uncovering hidden diversity and highlighting local endemism in the Western Ghats-Sri Lanka biodiversity hotspot.

Two novel genera and one new species of treefrog (Anura: Rhacophoridae) highlight cryptic diversity in the Western Ghats of India.

Amphibian diversity in the Western Ghats-Sri Lanka biodiversity hotspot is extremely high, especially for such a geographically restricted area. Frogs in particular dominate these assemblages, and the family Rhacophoridae is chief among these, with hundreds of endemic species. These taxa continue to be described at a rapid pace, and several groups have recently been found to represent unique evolutionary clades at the genus level. Here, we report DNA sequences, larval and breeding data for two species of rhacophorid treefrog (Polypedates bijui and a new, hitherto undescribed species). Remarkably, they represent unique, independent clades which form successive sister groups to the Pseudophilautus (Sri Lanka) + Raorchestes (India, China & Indochina) clades. We place these species into two new genera (Beddomixalus gen. nov. and Mercurana gen. nov.). Both of these genera exhibit a distinct reproductive mode among Rhacophoridae of peninsular India and Sri Lanka, with explosive breeding and semiterrestrial, unprotected, non-pigmented eggs oviposited in seasonal swamp pools, which hatch into exotrophic, free-living aquatic tadpoles. Relationships and representation of reproductive modes in sister taxa within the larger clade into which these novel genera are placed, is also discussed. These results suggest that more undescribed taxa may remain to be discovered in South Asia, and the crucial importance of conserving remaining viable habitats.

Mountain-associated clade endemism in an ancient frog family (Nyctibatrachidae) on the Indian subcontinent

Night frogs (Nyctibatrachidae) form a family endemic to the Western Ghats, a hill chain along the west coast of southern India. Extant members of this family are descendants of a lineage that originated on the subcontinent during its longtime isolation in the Late Cretaceous. Because the evolutionary history of Nyctibatrachidae has always been tightly connected to the subcontinent, these tropically-adapted frogs are an ideal group for studying how patterns of endemism originated and evolved during the Cenozoic in the Western Ghats. We used a combined set of mitochondrial and nuclear DNA fragments to investigate the phylogenetic relationships of 120 ingroup specimens of all known species of Nyctibatrachidae. Our analyses indicate that, although this family had an early origin on the Indian subcontinent, the early diversification of extant nyctibatrachids happened only in the Eocene. Biogeographic analyses show that dispersal across the Palghat gap and Shencottah gap was limited, which led to clade endemism within mountain ranges of the Western Ghats. It is likely that multiple biota have been affected simultaneously by these prominent geographical barriers. Our study therefore further highlights the importance of considering the Western Ghats–Sri Lanka biodiversity hotspot as an assemblage of distinct mountain regions, each containing endemism and deserving attention in future conservation planning.

Forest stand structure and composition in 96 sites along environmental gradients in the central Western Ghats of India

This data set reports woody plant species abundances in a network of 96 sampling sites spread across 22 000 km2 in the central Western Ghats region, Karnataka, India (74°15′–75°40′ E; 15°15′–13°30′ N). Due to its varied climate and diverse topography, the study area, which is part of the Western Ghats–Sri Lanka biodiversity hotspot, supports a wide array of non‐equatorial tropical habitats including wet evergreen, moist and dry deciduous, and intact as well as degraded forests and scrublands. These formations, floristically moderately rich and diversified, are characterized by a lower rate of endemism than in the southern part of the Western Ghats. This data paper provides abundance and girth data for 76 813 trees and lianas of 446 species collected in 96 sampling sites during 1996–1997. A total of 61 965 individuals ≥10‐cm girth at breast height (gbh) were recorded in 96 1‐ha macroplots, while 14 848 individuals &lt;10 cm gbh, but &gt;1 m height, were sampled in three 0.1‐ha microplots located within each macroplot. Additional data regarding the stand structure (average canopy height, percent canopy cover, number of strata) and the level of degradation are available for the macroplots, along with environmental data derived from other sources and analyses, such as soil types, rainfall, length of the dry season, and altitude. These data have been used to produce ecological research papers, as well as to elaborate conservation value maps and recommendations toward sustainable management of the forests of the central Western Ghats region.The complete data sets corresponding to abstracts published in the Data Papers section of the journal are published electronically in Ecological Archives at 〈http://esapubs.org/archive〉. (The accession number for each Data Paper is given directly beneath the title.)

Agrobiodiversity in a biodiversity hotspot: Kerala State, India. Its origin and status

This paper examines the status and characteristics of agrobiodiversity present in Kerala State, India, which is a part of the Western Ghats—Sri Lanka biodiversity hotspot. They show much heterogeneity. The State grows 142 crop plants belonging to 104 genera and 43 families. Almost the entire agrobiodiversity conservation work is being carried out by the central government, even though the states are also mandated to do this work. This appears to have an adverse effect on agrobiodiversity conservation. Until now, most attention was being paid to only the most important food and commercial crops, and very limited to their wild relatives and the less important crop plants.

Toad radiation reveals into-India dispersal as a source of endemism in the Western Ghats-Sri Lanka biodiversity hotspot

BackgroundHigh taxonomic level endemism in the Western Ghats-Sri Lanka biodiversity hotspot has been typically attributed to the subcontinent's geological history of long-term isolation. Subsequent out of – and into India dispersal of species after accretion to the Eurasian mainland is therefore often seen as a biogeographic factor that 'diluted' the composition of previously isolated Indian biota. However, few molecular studies have focussed on into-India dispersal as a possible source of endemism on the subcontinent. Using c. 6000 base pairs of mitochondrial and nuclear DNA, we investigated the evolutionary history and biogeography of true toads (Bufonidae), a group that colonized the Indian Subcontinent after the Indo-Asia collision.ResultsContrary to previous studies, Old World toads were recovered as a nested clade within New World Bufonidae, indicating a single colonization event. Species currently classified as Ansonia and Pedostibes were both recovered as being non-monophyletic, providing evidence for the independent origin of torrential and arboreal ecomorphs on the Indian subcontinent and in South-East Asia. Our analyses also revealed a previously unrecognized adaptive radiation of toads containing a variety of larval and adult ecomorphs. Molecular dating estimates and biogeographic analyses indicate that the early diversification of this clade happened in the Western Ghats and Sri Lanka during the Late Oligocene to Early Miocene.ConclusionPaleoclimate reconstructions have shown that the Early Neogene of India was marked by major environmental changes, with the transition from a zonal- to the current monsoon-dominated climate. After arrival in the Western Ghats-Sri Lanka hotspot, toads diversified in situ, with only one lineage able to successfully disperse out of these mountains. Consequently, higher taxonomic level endemism on the Indian Subcontinent is not only the result of Cretaceous isolation, but also of invasion, isolation and radiation of new elements after accretion to the Eurasian mainland.

Patterns in diversity of anurans along an elevational gradient in the Western Ghats, South India

AbstractAim To examine patterns in anuran species richness along an elevation gradient and identify factors that govern anuran species richness on a tropical elevational gradient.Location Sampling for anurans was carried out in Kalakad Mundanthurai Tiger Reserve (KMTR) in the southern Western Ghats, India.Methods Night‐time sampling for anuran species richness was carried out from 20 November 2004 to 20 April 2005, during the north‐east monsoon and dry seasons, using transects (50 × 2 m) and visual encounter surveys along the streams. The entire gradient was classified into thirteen 100‐m elevation zones. Sampling at the alpha (single drainage basin) level was carried out in the Chinnapul River drainage basin (40–1260 m a.s.l.) and at the gamma (landscape) level in four drainage basins. Additionally, published records were used to arrive at an empirical species richness (S) for the entire landscape. Mid‐Domain Null software was used to test for the possible influence of geometric constraints on anuran species at both the alpha and gamma levels. The influence of area under each elevation zone on empirical S was tested. The pattern in anuran species richness along the elevational gradient was investigated using: (1) species boundaries in each elevation zone and their habitat correlates, (2) abiotic factors as predictor variables, (3) mean snout vent lengths of anurans, and (4) correlation between the matrices of distance in the elevation zones based on microhabitat parameters and species composition. Cluster analysis on species presence–absence in the elevation zones was used to categorize the entire gradient into high, middle and low elevations. In these three elevation categories, pattern in composition of species was examined for endemism in Western Ghats–Sri Lanka biodiversity hotspot, uniqueness to an elevation zone, adaptations of adults and modes of breeding.Results Species richness at the alpha level increased linearly with elevation, while at the gamma level there were three peaks. Maximum species richness was observed at the highest elevation (1200 m) at both the alpha and the gamma levels. The observed patterns differed significantly from mid‐domain null predictions. The multi‐modal pattern in species richness was a consequence of overlapping species range boundaries. Soil temperature was the best single measure in explaining the majority of variation in species richness at the alpha level (r2 = 0.846, P &lt; 0.01). However, soil moisture was the best predictor when both the alpha and the gamma sites were pooled (r2 = 0.774, P &lt; 0.01). Anuran body size decreased with an increase in elevation. The highest proportions of endemic and unique species were found at high elevations (&gt; 700 m). The proportion of arboreal anurans increased from low to high elevation. Anurans exhibiting direct development were predominantly found at high elevations.Main conclusions Geometric constraints did not influence anuran species richness along the elevational gradient. Overlapping range boundaries influenced species richness at the gamma level. Abiotic factors such as soil temperature and moisture influenced anuran species richness in the mountain range. The ‘Massenerhebung effect’ could be responsible for range restriction and endemism of anurans, differences in guilds and mode of reproduction. These findings highlight the importance of cloud forests for endemic anurans.

Plant Community Structure in Tropical Rain Forest Fragments of the Western Ghats, India1

ABSTRACTChanges in tree, liana, and understory plant diversity and community composition in five tropical rain forest fragments varying in area (18–2600 ha) and disturbance levels were studied on the Valparai plateau, Western Ghats. Systematic sampling using small quadrats (totaling 4 ha for trees and lianas, 0.16 ha for understory plants) enumerated 312 species in 103 families: 1968 trees (144 species), 2250 lianas (60 species), and 6123 understory plants (108 species). Tree species density, stem density, and basal area were higher in the three larger (&gt; 100 ha) rain forest fragments but were negatively correlated with disturbance scores rather than area per se. Liana species density, stem density, and basal area were higher in moderately disturbed and lower in heavily disturbed fragments than in the three larger fragments. Understory species density was highest in the highly disturbed 18‐ha fragment, due to weedy invasive species occurring with rain forest plants. Nonmetric multidimensional scaling and Mantel tests revealed significant and similar patterns of floristic variation suggesting similar effects of disturbance on community compositional change for the three life‐forms. The five fragments encompassed substantial plant diversity in the regional landscape, harbored at least 70 endemic species (3.21% of the endemic flora of the Western Ghats–Sri Lanka biodiversity hotspot), and supported many endemic and threatened animals. The study indicates the significant conservation value of rain forest fragments in the Western Ghats, signals the need to protect them from further disturbances, and provides useful benchmarks for restoration and monitoring efforts.

Biodiversity in Sri Lanka and the Western Ghats

We read with interest the Report “Local endemism within the Western Ghats-Sri Lanka biodiversity hotspot” by F. Bossuyt et al. (15 Oct. 2004, p. [479][1]), which documents patterns of diversification in selected vertebrate and invertebrate lineages from Sri Lanka and the Western Ghats region of

Local endemism within the Western Ghats-sri Lanka biodiversity hotspot.

The apparent biotic affinities between the mainland and the island in the Western Ghats-Sri Lanka biodiversity hotspot have been interpreted as the result of frequent migrations during recent periods of low sea level. We show, using molecular phylogenies of two invertebrate and four vertebrate groups, that biotic interchange between these areas has been much more limited than hitherto assumed. Despite several extended periods of land connection during the past 500,000 years, Sri Lanka has maintained a fauna that is largely distinct from that of the Indian mainland. Future conservation programs for the subcontinent should take into account such patterns of local endemism at the finest scale at which they may occur.