Lanka Biodiversity Hotspot Research Articles

Forest species diversity and community composition in the northern Western Ghats, India

ABSTRACT Background The northern Western Ghats (NWG) – a part of the Western Ghats and Sri Lanka biodiversity hotspot supports tropical forests of conservation priority, due to anthropogenic intensification. Woody species diversity and ecology in NWG is poorly studied, necessitating the knowledge of spatial variability in species and underlying environmental factors, for effective conservation. Aims We described woody plant community composition and related it to climate data across a latitude of 1.4 degrees to obtain information about spatial and environmental variation to support protected area planning. Methods To estimate abundance, importance value index, diversity indices and rank – abundance, we recorded woody species in 144 plots across 12 sites. Elevation, temperature, rainfall, humidity data were related to diversity descriptors in a canonical correspondence analysis. Results We recorded 10,291 trees representing 187 species of 52 families. Divergent geo-climatic factors were related to distinct plant community structures, elevation and humidity being the most influential drivers of plant diversity and density. Numerous rare species were found restricted to environmentally distinct forests. Conclusion The wide-ranging environment and corresponding variations in forest community composition across the narrow latitudinal range of the study area revealed the importance of including such gradients in planning future protected areas in the NWG.

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.

Independent origins or single dispersal? Phylogenetic study supports early Cenozoic origin of three endemic Indo‐Sri Lankan Lygosomine skink genera

AbstractThe Western Ghats‐Sri Lanka biodiversity hotspot is home to three endemic Lygosomine (Reptilia, Scincidae) skink genera—Kaestlea, Ristella and Lankascincus. Phylogenetic reconstructions in the past have suggested a sister relationship between the Western Ghats endemic Ristella and the Sri Lankan endemic Lankascincus, while the placement of Kaestlea has been uncertain. We reconstruct a global, genus‐level, multi‐locus phylogeny of the sub‐family Lygosominae to ask if these endemic genera share an immediate common ancestor, that is, did they arise from a single dispersal event? Furthermore, to understand the possible centres of origin and dispersal routes of these three genera of Indo‐Sri Lankan skinks, we construct a time‐calibrated phylogeny and perform ancestral range evolution. We find that Kaestlea does not share an immediate ancestor with Ristella + Lankascincus. Therefore, their presence in the Indian subcontinent results from two independent colonization events. Both these dispersal events likely occurred during the late Palaeocene‐early Eocene from the Asian landmass. Our molecular dating and ancestral range evolution analyses add further evidence of probable transoceanic dispersal in skinks and early land connections between the Indian subcontinent and Asia. It also reveals that these skinks were some of the earliest lizards to disperse into the Indian subcontinent.

Checklist of Carabidae (Coleoptera) in the Chinnar Wildlife Sanctuary, a dry forest in the rain shadow region of the southern Western Ghats, India

The first report on the composition of carabids from a natural forest in peninsular India as well as from a dry forest belt in the rain shadow region of the Western Ghats is provided, with data on the subfamilies, tribes, genera, species, geographic range, collection techniques, and the relevant literature details for all the listed species. Fifty-four species belonging to 11 subfamilies and 31 genera were recorded. Harpalinae, Lebiinae, and Scaritinae with 15, 14, and seven species, respectively, are the species-rich subfamilies. The species list also includes two first records from India, four first records from southern India, and six species endemic to the Western Ghats and Sri Lanka biodiversity hot spot.

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.

A new ancient lineage of frog (Anura: Nyctibatrachidae: Astrobatrachinae subfam. nov.) endemic to the Western Ghats of Peninsular India.

The Western Ghats (WG) is an escarpment on the west coast of Peninsular India, housing one of the richest assemblages of frogs in the world, with three endemic families. Here, we report the discovery of a new ancient lineage from a high-elevation massif in the Wayanad Plateau of the southern WG. Phylogenetic analysis reveals that the lineage belongs to Natatanura and clusters with Nyctibatrachidae, a family endemic to the WG/Sri Lanka biodiversity hotspot. Based on geographic distribution, unique morphological traits, deep genetic divergence, and phylogenetic position that distinguishes the lineage from the two nyctibatrachid subfamilies Nyctibatrachinae Blommers-Schlösser, 1993 and Lankanectinae Dubois & Ohler, 2001, we erect a new subfamily Astrobatrachinae subfam. nov. (endemic to the WG, Peninsular India), and describe a new genus Astrobatrachus gen. nov. and species, Astrobatrachus kurichiyana sp. nov. The discovery of this species adds to the list of deeply divergent and monotypic or depauperate lineages with narrow geographic ranges in the southern massifs of the WG. The southern regions of the WG have long been considered geographic and climatic refugia, and this new relict lineage underscores their evolutionary significance. The small range of this species exclusively outside protected areas highlights the significance of reserve forest tracts in the WG in housing evolutionary novelty. This reinforces the need for intensive sampling to uncover new lineages and advance our understanding of the historical biogeography of this ancient landmass.

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.

Cololejeunea raduliloba Steph. (Marchantiophyta, Lejeuneaceae) from Assam, India

Cololejeunea raduliloba Steph., is collected from Gibbon Wildlife Sanctuary in Jorhat (Assam). In India, this species is little known and authentically reported only from Western Ghats and Sri Lanka biodiversity hotspot. In the Assam region, its presence was earlier doubted; hence present report confirms its occurrence in the region.

Effect of unmanaged harvests for the aquarium trade on the population status and dynamics of redline torpedo barb: A threatened aquatic flagship

Abstract The freshwater aquarium trade provides economic and livelihood opportunities to the rural poor, but has been implicated in biodiversity loss through population declines and local extirpation of high‐value endemic species. Previous observations on population declines are largely based on anecdotal data, however, and there are no studies on the population dynamics or stock assessment of freshwater fish species collected for the aquarium pet trade. To understand how wild collection of endemic and threatened species for the aquarium trade could affect their populations, the sustainability of collecting the endangered redline torpedo barb (Sahyadria denisonii), and its evolutionarily distinct lineages (henceforth RLTBs), from the Western Ghats region (part of the Western Ghats–Sri Lanka biodiversity hot spot) for the aquarium trade was studied to provide baseline data to inform conservation action. Local populations of RLTBs at the five commercial collection sites showed high mortality rates, and fish were exploited before they attained sexual maturity. The unmanaged fishery has led to unsustainable levels of exploitation, and populations of RLTBs at three sites are vulnerable to an impending collapse. Endemic and threatened freshwater fish species used in the aquarium pet trade are exposed to local extirpations and global extinctions unless management plans and legislative controls are implemented and strictly enforced. Management plans and conservation actions to help guide the responsible fisheries of RLTBs are suggested, and the wider implications of unmanaged exploitation of endemic aquarium fisheries are discussed.

Micro-habitat distribution drives patch quality for sub-tropical rocky plateau amphibians in the northern Western Ghats, India.

The importance of patch quality for amphibians is frequently overlooked in distribution models. Here we demonstrate that it is highly important for the persistence of endemic and endangered amphibians found in the threatened and fragile ecosystems that are the rocky plateaus in Western Maharashtra, India. These plateaus are ferricretes of laterite and characterise the northern section of the Western Ghats/Sri Lanka Biodiversity Hotspot, the eighth most important global hotspot and one of the three most threatened by population growth. We present statistically supported habitat associations for endangered and data-deficient Indian amphibians, demonstrating significant relationships between individual species and their microhabitats. Data were collected during early monsoon across two seasons. Twenty-one amphibian taxa were identified from 14 lateritic plateaus between 67 and 1179m above sea level. Twelve of the study taxa had significant associations with microhabitats using a stepwise analysis of the AICc subroutine (distLM, Primer-e, v7). Generalist taxa were associated with increased numbers of microhabitat types. Non-significant associations are reported for the remaining 9 taxa. Microhabitat distribution was spatially structured and driven by climate and human activity. Woody plants were associated with 44% of high-elevation taxa. Of the 8 low-elevation taxa 63% related to water bodies and 60% of those were associated with pools. Rock size and abundance were important for 33% of high elevation specialists. Three of the 4 caecilians were associated with rocks in addition to soil and stream presence. We conclude the plateaus are individualistic patches whose habitat quality is defined by their microhabitats within climatic zones.

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.

An annotated checklist and a family key to the pseudoscorpion fauna (Arachnida: Pseudoscorpiones) of Sri Lanka.

Sri Lanka is part of the Western Ghats & Sri Lanka biodiversity hotspot. Thus, the conservation of Sri Lanka's unique biodiversity is crucial. The current study is part of an ongoing survey of pseudoscorpion fauna of Sri Lanka. We carried out an island-wide survey of pseudoscorpions using a range of collection methods to sample a diverse set of habitats around the country. This produced 32 species, four of which might be new to science, belonging to 25 genera. The family Cheiridiidae was discovered on the island for the first time. One new combination, Indogarypus ceylonicus (Beier, 1973) comb. nov., is proposed. Out of the 47 species now recorded, 20 (43 %) are potentially endemic to Sri Lanka. We provide a checklist of all known species, document their distribution and give a key to the families.

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.