80 research outputs found
tale of two islands. The reality of large-scale extinction in the early stages of the Anthropocene: a lack of awareness and appropriate action
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
Saving living diversity in the face of the unstoppable 6th mass extinction: A call for urgent international action
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
Review of the genus Endothyrella Zilch, 1960 with description of five new species (Gastropoda, Pulmonata, Plectopylidae)
All known taxa of the genus Endothyrella Zilch, 1960 (family Plectopylidae) are reviewed. Altogether 23 Endothyrella species are recognized. All species are illustrated and whenever possible, photographs of the available type specimens are provided. Five new species are described: E. angulata Budha & Páll-Gergely, sp. n., E. dolakhaensis Budha & Páll-Gergely, sp. n. and E. nepalica Budha & Páll-Gergely, sp. n. from Nepal, E. robustistriata Páll-Gergely, sp. n. from the Naga Hills, India, and E. inexpectata Páll-Gergely, sp. n. from Sichuan, China. Helix (Plectopylis) munipurensis Godwin-Austen, 1875 is synonymized with Helix (Plectopylis) serica Godwin-Austen, 1875, and Plectopylis (Endothyra) gregorsoni Gude, 1915 is synonymized with Helix (Plectopylis) macromphalus W. Blanford, 1870. Plectopylis plectostoma var. exerta Gude, 1901 is a synonym of Plectopylis plectostoma var. tricarinata Gude, 1896, which is a species in its own right. Five species of the genus Chersaecia viz. Plectopylis (Chersaecia) bedfordi Gude, 1915, Helix (Plectopylis) brahma Godwin-Austen, 1879, Helix (Plectopylis) Oglei Godwin-Austen, 1879, Helix (Plectopylis) serica Godwin-Austen, 1875, and Plectopylis (Endothyra) williamsoni Gude, 1915 are moved to Endothyrella. The holotype of Plectopylis hanleyi Godwin-Austen, 1879 seems to be lost; therefore, P. hanleyi is considered to be a nomen dubium.ArticleZOOKEYS. (529):1-70 (2015)journal articl
Molecular phylogeny of the Achatinoidea (Mollusca: Gastropoda)
This study presents a multi-gene phylogenetic analysis of the Achatinoidea and provides an initial basis for a taxonomic re-evaluation of family level groups within the superfamily. A total of 5028 nucleotides from the nuclear rRNA, actin and histone 3 genes and the 1st and 2nd codon positions of the mitochondrial cytochrome c oxidase subunit I gene were sequenced from 24 species, representing six currently recognised families. Results from maximum likelihood, neighbour joining, maximum parsimony and Bayesian inference trees revealed that, of currently recognised families, only the Achatinidae are monophyletic. For the Ferussaciidae, Ferussacia folliculus fell separately to Cecilioides gokweanus and formed a sister taxon to the rest of the Achatinoidea. For the Coeliaxidae, Coeliaxis blandii and Pyrgina umbilicata did not group together. The Subulinidae was not resolved, with some subulinids clustering with the Coeliaxidae and Thyrophorellidae. Three subfamilies currently included within the Subulinidae based on current taxonomy likewise did not form monophyletic groups
Systematics of the family Plectopylidae in Vietnam with additional information on Chinese taxa (Gastropoda, Pulmonata, Stylommatophora)
Vietnamese species from the family Plectopylidae are revised based on the type specimens of all known taxa, more than 600 historical non-type museum lots, and almost 200 newly-collected samples. Altogether more than 7000 specimens were investigated. The revision has revealed that species diversity of the Vietnamese Plectopylidae was previously overestimated. Overall, thirteen species names (anterides Gude, 1909, bavayi Gude, 1901, congesta Gude, 1898, fallax Gude, 1909, gouldingi Gude, 1909, hirsuta Möllendorff, 1901, jovia Mabille, 1887, moellendorffi Gude, 1901, persimilis Gude, 1901, pilsbryana Gude, 1901, soror Gude, 1908, tenuis Gude, 1901, verecunda Gude, 1909) were synonymised with other species. In addition to these, Gudeodiscus hemmeni sp. n. and G. messageri raheemi ssp. n. are described from north-western Vietnam. Sixteen species and two subspecies are recognized from Vietnam. The reproductive anatomy of eight taxa is described. Based on anatomical information, Halongella gen. n. is erected to include Plectopylis schlumbergeri and P. fruhstorferi. Additionally, the genus Gudeodiscus is subdivided into two subgenera (Gudeodiscus and Veludiscus subgen. n.) on the basis of the morphology of the reproductive anatomy and the radula. The Chinese G. phlyarius werneri Páll-Gergely, 2013 is moved to synonymy of G. phlyarius. A spermatophore was found in the organ situated next to the gametolytic sac in one specimen. This suggests that this organ in the Plectopylidae is a diverticulum. Statistically significant evidence is presented for the presence of calcareous hook-like granules inside the penis being associated with the absence of embryos in the uterus in four genera. This suggests that these probably play a role in mating periods before disappearing when embryos develop. Sicradiscus mansuyi is reported from China for the first time.ArticleZOOKEYS. (473):1-118 (2015)journal articl
Phylogenetic insights into the terrestrial snails Helicoidei (Gastropoda: Stylommatophora) with special emphasis on the Camaenidae
The superfamily Helicoidei are a widely distributed and diverse infraorder of land snails and slugs. Here, we constructed a phylogenetic tree based on sequences of the large subunit ribosomal RNA gene to investigate the relationships within the Helicoidei. Based on our phylogenetic tree, the family Camaenidae, as currently recognized, is not monophyletic, with the Polygyridae falling within the group. Likewise, the family Hygromiidae as currently defined is not monophyletic and incorporates the Geomitridae. The family Xanthoncyhidae form a monophyletic group that is sister to the Pleurodontidae. Likewise, the family Helicidae form a monophyletic group; it is sister to the branch incorporating Hygromiidae, Geomitridae, Pleurodontidae, Helicodontidae, and Xanthonychidae. The Solaropsidae are the sister group to a clade comprising other Sagdoidea. Our findings suggest that the Hygromiidae s.l. families should be restored to their previous name, Hygromiidae. A new genus of Bradybaeninae, Jiaoliaous Zhang gen. nov., is described here, with a simple genital system, single dart sac with multi-branched mucous glands, and a penis with a penial sheath
Phylogenetics and species delimitations of the operculated land snail Cyclophorus volvulus (Gastropoda: Cyclophoridae) reveal cryptic diversity and new species in Thailand
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
Redescription of Acmella tersa (Benson, 1853), the Type Species of Acmella W.T. Blanford, 1869 (Gastropoda: Assimineidae), from Meghalaya, Northeast India
The type species of the assimineid genus Acmella W.T. Blanford, 1869 is Cyclostoma tersum Benson, 1853, originally described from ‘Musmai’ [Mawsmai], Meghalaya, Northeast India. No specimens from Benson’s type series can be traced, and contemporary shells collected from the type locality in museum collections are extremely worn. It has therefore been impossible to examine shell microsculpture, an important taxonomic character in the diagnosis of species of Assimineidae, using museum specimens. In order to provide better diagnostic characters for the genus Acmella, we redescribe and illustrate Acmella tersa from newly collected specimens, one of which is designated as the neotype. We also provide a list of all known species attributed to Acmella
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