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Recent conceptual and practical advances in phylogenetic species delimitation have enabled progressively robust biodiversity studies. Delimiting species in widespread taxa is an intriguing problem; the edible operculated land snail Cyclophorus volvulus (Müller, 1774) is a good example since it shows a high degree of shell and color variation along with a widespread distribution throughout Thailand. Taxonomic boundaries for C . volvulus were examined and clarified using a combined morphological and phylogenetic approach, the latter of which was based on both nuclear and mitochondrial gene sequences. Moreover, three species delimitation analyses were applied: Poisson tree processes (PTP), automatic barcode gap discovery (ABGD), and generalized mixed Yule-coalescent (GMYC). All phylogenetic trees revealed that C . volvulus was polyphyletic and comprised of three clades that coincided with their geographic distribution. The three species delimitation analyses concurred with the phylogenies and formed at least three groups. According to the results, C . volvulus s.l., as currently recognized, consists of three distinct species in Thailand: C . volvulus s.s., C . occultus sp. nov., and C . borealis sp. nov., which are described herein. Moreover, several of these highly distinct C . volvulus evolutionarily significant units (ESU) are likely to require urgent conservation attention.

The endemic biotas of oceanic islands were vulnerable and many have been lost. The more ancient, complex and dynamic biotas of continents were more resilient but are now being obliterated. Sumatra and Madagascar are large continental plate islands with very different histories and biotas that exemplify the situation on continental land masses. Both tropical islands have suffered massive habitat loss and species extinction from human population pressure, Sumatra mostly from global and Madagascar from local pressure. Snails demonstrate the complex history of faunal origins as illustrated by the relationships between Madagascan, Indian and southeast Asian snail faunas and their plate tectonic geological history. Snails also reveal our limited knowledge of the details but not the scope of extinctions through habitat loss. International agencies are failing to address the root causes of natural habitat loss and consequent extinctions, which are overpopulation and an economic system based on perpetual growth. The fallacy of sustainable development and the limitations of current conservation practice are addressed. Recognition that we cannot stop extinctions in the immediate future demands a new, supplementary approach to conservation based on advances in molecular technology.

The global scale and impact of current and increasing human population size is incompatible with the survival of biological diversity and the 6th mass extinction cannot be stopped. For the vast majority of species we have neither the knowledge of when they will go extinct nor the capacity to find out. Conventional conservation measures can only amount to token damage limitation. Advances in molecular biology allow low cost options for storing the genetic diversity of numerous species and maximising future options for restoring species.

Limestone karsts can form terrestrial habitat islands for calcium-dependent organisms. In Vietnam, many karst habitats are threatened, while their rich biodiversity is still far from being thoroughly explored. Given that conservation of karst biota strongly relies on correct species identification, the presence of undetected cryptic species can pose severe problems. The present study focuses on cryptic diversity among karst-inhabiting land snails of the genus Cyclophorus in northern Vietnam, where specimens with a similar shell morphology have been reported from various regions. In order to examine the diversity and evolutionary history of this \"widespread morphotype\", we generated a Bayesian phylogeny based on DNA sequence data. Automatic Barcode Gap Discovery (ABGD) and the Bayesian implementation of the Poisson tree processes model (bPTP) contributed to species delimitation and analyses of shell shape and size aided the morphological characterisation of individual species. We found that the examined specimens of the widespread morphotype did not form a single monophyletic group in the phylogeny but clustered into several different clades. We delimited nine different species that develop the widespread morphotype and described four of them as new. Processes of convergent evolution were probably involved in the origin of the delimited species, while their generally allopatric distribution could result from interspecific competition. Our findings indicate ongoing processes of speciation and a potential case of morphological character displacement. The high degree of morphological overlap found among the species underlines the importance of DNA sequence data for species delimitation and description in the genus Cyclophorus. Given the findings of the present study and the high potential that as yet undiscovered cryptic taxa have also evolved in other groups of karst-inhabiting organisms, we argue for a systematic and efficient detection and description of Vietnam's karst biodiversity to provide a solid basis for future conservation planning.

The Giant African Land Snail, Achatina ( =  Lissachatina) fulica Bowdich, 1822, is a tropical crop pest species with a widespread distribution across East Africa, the Indian subcontinent, Southeast Asia, the Pacific, the Caribbean, and North and South America. Its current distribution is attributed primarily to the introduction of the snail to new areas by Man within the last 200 years. This study determined the extent of genetic diversity in global A. fulica populations using the mitochondrial 16S ribosomal RNA gene. A total of 560 individuals were evaluated from 39 global populations obtained from 26 territories. Results reveal 18 distinct A. fulica haplotypes; 14 are found in East Africa and the Indian Ocean islands, but only two haplotypes from the Indian Ocean islands emerged from this region, the C haplotype, now distributed across the tropics, and the D haplotype in Ecuador and Bolivia. Haplotype E from the Philippines, F from New Caledonia and Barbados, O from India and Q from Ecuador are variants of the emergent C haplotype. For the non-native populations, the lack of genetic variation points to founder effects due to the lack of multiple introductions from the native range. Our current data could only point with certainty to the Indian Ocean islands as the earliest known common source of A. fulica across the globe, which necessitates further sampling in East Africa to determine the source populations of the emergent haplotypes.

This is the very first checklist of the terrestrial gastropods of Nepal. It includes 138 species and six subspecies, of which 22 species are endemic and four are introduced. It highlights 34 species recorded for the first time in Nepal and provides new distribution records for another 30 species.

Here, the clarification of the \"type\" status for Cyclophorus (Glossostylus) koboensis Godwin-Austen, 1915 catalogued by Nantarat et al. (2014) is corrected and briefly discussed.Here, the clarification of the \"type\" status for Cyclophorus (Glossostylus) koboensis Godwin-Austen, 1915 catalogued by Nantarat et al. (2014) is corrected and briefly discussed.

Since the time of the original description there have been no precise locality records in Cambodia of Bertia cambojiensis (Reeve, 1860) and it was believed to be extinct. In 2012, a joint Natural History Museum survey with Vietnamese colleagues rediscovered living populations of this huge sinistral helicoid snail in a protected area of southern Vietnam. The genitalia and radula morphology are re-assessed and type specimens of all recognised congeners are figured herein. The unique morphological characters of this species are a small and simple penis, well-developed amatorial organ complex that incorporates four amatorial organ ducts, a short gametolytic organ complex and spiked papilla, and radula morphology with unicuspid teeth. The type locality of B. cambojiensis , which has been contentious, is determined here to be in the vicinity of ‘Brelum’, Vietnam, near the border with Cambodia. In addition, the nucleotide sequences of barcoding genes COI, 16SrRNA and 28S fragments were provided for further comparison.

The insular limestone karsts of northern Vietnam harbor a very rich biodiversity. Many taxa are strongly associated with these environments, and individual species communities can differ considerably among karst areas. The exact processes that have shaped the biotic composition of these habitats, however, remain largely unknown. In this study, the role of two major processes for the assembly of snail communities on limestone karsts was investigated, interspecific competition and filtering of taxa due to geographical factors. Communities of operculate land snails of the genus Cyclophorus were studied using the dry and fluid‐preserved specimen collections of the Natural History Museum, London. Phylogenetic distances (based on a Bayesian analysis using DNA sequence data) and shell characters (based on 200 semilandmarks) were used as proxies for ecological similarity and were analyzed to reveal patterns of overdispersion (indicating competition) or clustering (indicating filtering) in observed communities compared to random communities. Among the seven studied karst areas, a total of 15 Cyclophorus lineages were found. Unique communities were present in each area. The analyses revealed phylogenetic overdispersion in six and morphological overdispersion in four of seven karst areas. The pattern of frequent phylogenetic overdispersion indicated that competition among lineages is the major process shaping the Cyclophorus communities studied. The Coastal Area, which was phylogenetically overdispersed, showed a clear morphological clustering, which could have been caused by similar ecological adaptations among taxa in this environment. Only the community in the Cuc Phuong Area showed a pattern of phylogenetic clustering, which was partly caused by an absence of a certain, phylogenetically very distinct group in this region. Filtering due to geographical factors could have been involved here. This study shows how museum collections can be used to examine community assembly and contributes to the understanding of the processes that have shaped karst communities in Vietnam. In this study, the processes underlying community assembly of land snails (Cyclophorus spp.) on northern Vietnam's island‐like limestone karsts were investigated based on museum collection material. Characters from molecular phylogenetics and shell morphology were used as proxies for ecological similarity and analyzed for patterns of overdispersion (indicating competition) or clustering (indicating filtering) in communities. Unique communities were present in each of the studied karst areas, and most of them have probably been shaped by competition rather than by filtering due to geographical factors.

Eleven species of Glessulinae belonging to the genera Martens, 1860 (three species) and Godwin-Austen, 1920 (eight species) are reported from Nepal, six of which are new to science and are described here, viz., Budha & Backeljau, , Budha & Backeljau, , Budha & Naggs, , Budha & Naggs, , Budha & Naggs and Budha, and two are new records for Nepal viz. G. cf. hebetata and R. cf. mastersi. The relation between the shell height-width ratio and the structure of the proximal part of the male reproductive organs in Glessulinae is explored. Illustrations and a key for the identification of the Nepalese Glessulinae are provided, including the first record of a spermatophore in .