ORCID Profile
0000-0002-4599-6724
Current Organisation
Guangxi University
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Cold Spring Harbor Laboratory
Date: 14-08-2023
DOI: 10.1101/2023.08.12.549244
Abstract: Ecomorphs result from ergent natural selection, leading to species-rich adaptive radiations. Identifying ecomorphs and the resulting adaptive radiations in frogs is challenging due to conserved morphology and high species ersity. In this study, we demonstrate the ecological and climate specializations that have driven the ersification of shrub frogs of the genus Pseudophilautus in Sri Lanka, a tropical continental island. We use a time-calibrated phylogeny, morphometric analyses, and climate-niche evolution, and identify five ecomorphological categories, including Tree-shrub, Rock-boulder, Leaf-litter, Habitat Generalists, and Canopy forms, and describe their evolution. Body size is the primary factor separating species, and specific body features correlate with habitat type. Ecomorphs likely evolved multiple times in disparate lineages, and in different regions and altitudes, during cold climatic periods owing to monsoon cycles resulting from the Himalayan-Tibetan orogeny. The common ancestor was a medium-sized, wet-adapted, tree-shrub habitat specialist which originated in the late Oligocene. Extreme size classes (diminutive leaf litter forms and large canopy forms) evolved recently and suggest that morphological disparity arose late in ersification, possibly aided by favorable climates. This work will facilitate understanding of adaptive radiations in frogs, which possibly will help uncover the prevalence of subtle adaptive radiations in frogs, just as in tailed-vertebrates.
Publisher: Public Library of Science (PLoS)
Date: 16-08-2011
Publisher: Magnolia Press
Date: 23-08-2018
DOI: 10.11646/ZOOTAXA.4461.4.4
Abstract: The monotypic genus Lankanectes, considered an evolutionary long branch with India’s Nyctibatrachus as its sister lineage, is represented by L. corrugatus, a species widely distributed within the wet zone of Sri Lanka up to 1500 m asl, where it inhabits a variety of lotic and lentic habitats. Here, following an integrative taxonomic approach using DNA-based phylogenies, morphology, morphometry, and ecological niche models, we describe a new species—Lankanectes pera sp. nov. The new species is distinguished from its sister species mainly by its tuberculated throat and absence of dark patches on venter, throat, manus and pes. The uncorrected genetic distances between the two Lankanectes species for a fragment of the non-coding mitochondrial 16S rRNA gene is 3.5–3.7%. The new species has a very restricted climatic distribution with a total predicted area of only 360 km2 (vs. 14,120 km2 for L. corrugatus). Unlike L. corrugatus, which prefers muddy substrates and marshy areas, the new species is observed inhabiting only pristine streams flowing through canopy covered montane forests in the highest reaches of the Knuckles Mountain range. The specialized new species will need immediate conservation attention due to its restricted distribution (montane isolate), specialized habit of inhabiting clear mountain streams, and small population size.
Publisher: PeerJ
Date: 20-12-2018
DOI: 10.7717/PEERJ.6084
Abstract: A recent (2013) taxonomic review of the freshwater-fish genus Rasboroides , which is endemic to Sri Lanka, showed it to comprise four species: R. vaterifloris , R. nigromarginatus , R. pallidus and R. rohani. Here, using an integrative-taxonomic analysis of morphometry, meristics and mitochondrial DNA sequences of cytochrome b ( cytb ) and cytochrome oxidase subunit 1 ( coi ), we show that R. nigromarginatus is a synonym of R. vaterifloris , and that R. rohani is a synonym of R. pallidus. The creation and recognition of unnecessary taxa (‘taxonomic inflation’) was in this case a result of selective s ling confounded by a disregard of allometry. The population referred to R. rohani in the Walawe river basin represents an undocumented trans-basin translocation of R. pallidus , and a translocation into the Mahaweli river of R. vaterifloris , documented to have occurred ca 1980, in fact involves R. pallidus. A shared haplotype suggests the latter introduction was likely made from the Bentara river basin and not from the Kelani, as claimed. To stabilize the taxonomy of these fishes, the two valid species, R. vaterifloris and R. pallidus , are diagnosed and redescribed, and their distributions delineated. We draw attention to the wasteful ersion of conservation resources to populations resulting from undocumented translocations and to taxa resulting from taxonomic inflation. We argue against translocations except where mandated by a conservation emergency, and even then, only when supported by accurate documentation.
Publisher: American Association for the Advancement of Science (AAAS)
Date: 15-10-2004
Abstract: The apparent biotic affinities between the mainland and the island in the Western Ghats–Sri Lanka bio ersity 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.
Publisher: American Association for the Advancement of Science (AAAS)
Date: 11-10-2002
Publisher: Cold Spring Harbor Laboratory
Date: 13-05-2022
DOI: 10.1101/2022.05.13.491758
Abstract: Climate change and infectious diseases continue to drive global hibian population declines, contributing to one of the greatest vertebrate extinctions of the Anthropocene. Currently around 16% hibian species across the world are affected by four pathogens – Batrachochytrium dendrobatidis ( Bd ), B. salamandrivorans ( Bsal ), Ranavirus and Perkinsea . A climatic context behind the dispersal of some of these diseases is hypothesized. However, the interplay between niche conservatism (NC) and climatic niche evolution (CNE), essential to understand disease evolution and dispersal, has so far received little attention. Here we show that the impacts of hibian pathogens are intensifying as their climatic niches evolve. NC-based analyses suggest that niches of these diseases overlap, especially in Europe and East/southeast Asia (ESEA), and that all four pathogens will continue to devastate hibians through seasonality shifts and range expansions, penetrating deeper into temperate regions and global hibian ersity hotspots. Bd will spread over ersity-rich mountain ranges and ranaviruses will overwhelm lowlands. CNE-based analyses suggest that the earliest lineages of these diseases originated in colder regions and that some lineages subsequently evolved towards warmer climatic niches. We caution that quiescent, warm-adapted strains are likely to become widespread and novel ranaviruses adapted to local climatic conditions and new hosts are likely to emerge. These results portend the dangers of introducing pathogens into new regions given their ability to adapt to changing climate scenarios. In a climatic background conducive to most of these diseases, frequent monitoring, enhanced biosecurity measures and policy reforms are needed for disease control and mitigation.
Publisher: Senckenberg Gesellschaft für Naturforschung
Date: 2020
Publisher: Pensoft Publishers
Date: 28-01-2019
DOI: 10.3897/ZOOKEYS.820.29632
Abstract: Morphological and molecular analyses of specimens representative of the geographic range of the cyprinid genus Amblypharyngodon in Sri Lanka suggest the presence of only a single species in the island, for which the name Amblypharyngodongrandisquamis Jordan & Starks, 1917, is available. Amblypharyngodongrandisquamis is a species endemic to Sri Lanka, distributed across the lowlands of both of the island’s main climatic zones. It is distinguished from all other species of Amblypharyngodon , including the three species recorded from peninsular India ( A.mola , A.microlepis , and A.melettinus ), by a suite of characters that includes a body depth of 26.9–31.2% of the standard length (SL), 42–56 scales in the lateral series (of which usually 8–16 are pored), 20–24 circumpeduncular scales, 14–17 scale rows between the origins of the dorsal and pelvic fins, a dorsal-fin height of 21.1–27.6% SL, 18–19 caudal vertebrae and an eye diameter of 22.7–30.5% of the head length. Amblypharyngodongrandisquamis differs from A.melettinus and A.mola by uncorrected pairwise genetic distances of more than 9% and 6%, respectively, for the mitochondrial cytochrome oxidase subunit 1 (COI) gene.
Publisher: Magnolia Press
Date: 14-09-2020
DOI: 10.11646/ZOOTAXA.4852.1.10
Abstract: Invasive alien species (IAS) are a major threat to bio ersity and have contributed to population declines in native species worldwide (Vilà et al. 2011 Gurevitch & Padilla 2004). IUCN’s Invasive Species Specialist Group lists some 80 invasive or potentially invasive species in Sri Lanka, which is part of a global bio ersity hotspot (Myers et al. 2000 Marambe et al. 2011). The major release of aquatic IAS on the island are routed through the ornamental-fish industry (Marambe et al. 2011 Sudasinghe 2016), though a minority represents deliberate, if unplanned, introductions by governmental and non-governmental agencies (Marambe et al. 2011).
Publisher: Informa UK Limited
Date: 20-02-2015
Publisher: Elsevier BV
Date: 03-2019
DOI: 10.1016/J.YMPEV.2018.11.004
Abstract: Pseudophilautus comprises an endemic ersification predominantly associated with the wet tropical regions of Sri Lanka that provides an opportunity to examine the effects of geography and historical climate change on ersification. Using a time-calibrated multi-gene phylogeny, we analyze the tempo of ersification in the context of past climate and geography to identify historical drivers of current patterns of ersity and distribution. Molecular dating suggests that the ersification was seeded by migration across a land-bridge connection from India during a period of climatic cooling and drying, the Oi-1 glacial maximum around the Eocene-Oligocene boundary. Lineage-through-time plots suggest a gradual and constant rate of ersification, beginning in the Oligocene and extending through the late Miocene and early Pliocene with a slight burst in the Pleistocene. There is no indication of an early-burst phase of ersification characteristic of many adaptive radiations, nor were there bursts of ersification associated with favorable climate shifts such as the intensification of monsoons. However, a late Miocene (8.8 MYA) back-migration to India occurred following the establishment of the monsoon. The back migration did not trigger a ersification in India similar to that manifest in Sri Lanka, likely due to occupation of available habitat, and consequent lack of ecological opportunity, by the earlier radiation of a sister lineage of frogs (Raorchestes) with similar ecology. Phylogenetic area reconstructions show a pattern of sister species distributed across adjacent mountain ranges or from different parts of large montane regions, highlighting the importance of isolation and allopatric speciation. Hence, local species communities are composed of species from disparate clades that, in most cases, have been assembled through migration rather than in situ speciation. Lowland lineages are derived from montane lineages. Thus, the hills of Sri Lanka acted as species pumps as well as refuges throughout the 31 million years of evolution, highlighting the importance of tropical montane regions for both the generation and maintenance of bio ersity.
Publisher: Research Square Platform LLC
Date: 14-07-2023
DOI: 10.21203/RS.3.RS-3165240/V1
Abstract: Sri Lanka’s biota is derived largely from Southeast Asian lineages which immigrated via India following its early-Eocene contact with Laurasia. The island is now separated from southeastern India by the 30 km wide Palk Strait which, during sea-level low-stands, was bridged by the 140 km-wide Palk Isthmus. Consequently, biotic ingress and egress were mediated largely by the climate of the isthmus. Because of their dependence on perennial aquatic habitats, freshwater fish are useful models for biogeographic studies. Here we investigate the timing and dynamics of the colonization of—and ersification on—Sri Lanka by a group of four closely-related genera of cyprinid fishes ( Puntius sensu lato). We construct a molecular phylogeny based on two mitochondrial and two nuclear gene markers, conduct ergence timing analyses and ancestral-range estimations to infer historical biogeography, and use haplotype networks to infer phylogeographic patterns. The origin of Puntius s.l. is dated to ~20 Ma. The source of ersification of Puntius s.l. is Sri Lanka-Peninsular India. Species confined to perhumid rainforests show strong phylogeographic structure, while habitat generalists show little or no such structure. Ancestral range estimations for Plesiopuntius bimaculatus and Puntius dorsalis support an ‘Out of Sri Lanka’ scenario. Sri Lankan Puntius s.l. derive from multiple migrations across the Palk Isthmus between the early Miocene and the late Pleistocene. Species dependent on an aseasonal climate survived aridification in rainforest refugia in the island’s perhumid southwest and went on to recolonize the island and even southern India when pluvial conditions resumed. Our results support an historical extinction of Sri Lanka’s montane aquatic fauna, followed by a recent partial recolonization of the highlands, showing also that headwater stream capture facilitated dispersal across basin boundaries.
Publisher: Magnolia Press
Date: 19-01-2015
DOI: 10.11646/ZOOTAXA.3911.2.6
Abstract: The bufonid genus Adenomus, an endemic of the montane and lowland rainforests of central and south-western Sri Lanka, has been considered to comprise of three species, viz. A. kelaartii, A. dasi and A. kandianus, the last of which has been recently highlighted as "the world's rarest toad". We conducted a survey across the known range of Adenomus and used multiple criteria to delineate species boundaries within the genus. These include: a molecular phylogeny based on a 16S ribosomal RNA gene fragment an examination of the external morphology of adults and larvae, and the skeletal morphology of adults a bioacoustic analysis and ecological niche modelling. We show that Adenomus is monophyletic and that it comprises only two species: A. kelaartii and A. kandianus, with A. dasi being a junior synonym of the latter. For the two valid species of Adenomus, we provide detailed osteological descriptions clarify the distribution patterns and provide genetic data to facilitate their scientific conservation management.
Publisher: Hindawi Limited
Date: 03-08-2020
DOI: 10.1111/JZS.12395
Publisher: Springer Science and Business Media LLC
Date: 04-10-2023
Publisher: Elsevier BV
Date: 08-2020
Publisher: Springer Science and Business Media LLC
Date: 29-09-2021
Publisher: Elsevier BV
Date: 12-2013
Publisher: Wiley
Date: 30-08-2020
DOI: 10.1111/ZSC.12445
Publisher: Cold Spring Harbor Laboratory
Date: 24-09-2021
DOI: 10.1101/2021.09.22.461377
Abstract: Although large ersifications of species occur unevenly across space and evolutionary lineages, the relative importance of their driving mechanisms, such as climate, ecological opportunity and key innovations, remains poorly understood. Here, we explore the remarkable ersification of rhacophorid frogs, which represent six percent of global hibian ersity, utilize four distinct reproductive modes, and span a climatically variable area across mainland Asia, associated continental islands, and Africa. Using a complete species-level phylogeny, we find near-constant ersification rates but a highly uneven distribution of species richness. Montane regions on islands and some mainland regions have higher phylogenetic ersity and unique assemblages of taxa we identify these as cool-wet refugia. Starting from a centre of origin, rhacophorids reached these distant refugia by adapting to new climatic conditions (‘niche evolution’-dominant), especially following the origin of key innovations such as terrestrial reproduction (in the Late Eocene) or by dispersal during periods of favourable climate (‘niche conservatism’-dominant).
No related grants have been discovered for Madhava Meegaskumbura.