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From sea to land and beyond – New insights into the evolution of euthyneuran Gastropoda (Mollusca)
Annette Klussmann-Kolb, Angela Dinapoli, Kerstin Kuhn, Bruno Streit, Christian Albrecht
BMC Evolutionary Biology , 2008, DOI: 10.1186/1471-2148-8-57
Abstract: We found several well supported clades within Euthyneura, however, we could not confirm the traditional classification, since Pulmonata are paraphyletic and Opistobranchia are either polyphyletic or paraphyletic with several clades clearly distinguishable. Sacoglossa appear separately from the rest of the Opisthobranchia as sister taxon to basal Pulmonata. Within Pulmonata, Basommatophora are paraphyletic and Hygrophila and Eupulmonata form monophyletic clades. Pyramidelloidea are placed within Euthyneura rendering the Euthyneura paraphyletic.Based on the current phylogeny, it can be proposed for the first time that invasion of freshwater by Pulmonata is a unique evolutionary event and has taken place directly from the marine environment via an aquatic pathway. The origin of colonisation of terrestrial habitats is seeded in marginal zones and has probably occurred via estuaries or semi-terrestrial habitats such as mangroves.Within the phylum Mollusca, Gastropoda represent the largest and most diverse group in terms of species numbers, niche selection and life history strategies. They have been traditionally classified into three main subclasses: Prosobranchia, Opisthobranchia and Pulmonata [1-3]. Within Gastropoda, Opisthobranchia and Pulmonata have been united as Euthyneura and have since Spengel [4] been contrasted to the Streptoneura (= Prosobranchia). The latter, however, are commonly accepted as being paraphyletic [5].Although a plethora of morphological and anatomical data on Gastropoda have accumulated over the last centuries, it was not until the 1980s that the development of cladistic methodology allowed for analysing these data in a phylogenetic framework e. g. [5-9]. Nevertheless, euthyneuran gastropods have often been neglected in these studies.Several new studies based on morphological data have indicated that Euthyneura is a taxon clearly distinct from the remaining Gastropoda, belonging to a larger monophyletic group, the Heterobranchia. The latter al
José R. Stuardo,Patricio Vargas-Almonacid
Gayana (Concepción) , 2000,
Abstract: Se examina el status taxonómico de las especies chilenas de las familias Veronicellidae, Pupillidae y Achatinellidae, como parte de una serie de análisis taxonómicos sobre los moluscos terrestres de Chile que se elabora como seguimiento a la sinopsis del grupo publicada con anterioridad (Stuardo & Vega 1985). Son pocos los trabajos trascendentes publicados después de la sinopsis. En la actualidad hay descritas dos especies de Veronicellidae, dos de Pupillidae y 21 especies de Achatinellidae. De éstas, el único registro de Chile para Heterovaginina limayana Lesson es cuestionable y la subespecie Pupoides (Ischnopupoides) minimus costatus Biese, es considerada inválida. Se presenta una exhaustiva compilación de la sinonimia, junto a una discusión morfológica de los caracteres de la concha y de la distribución topotípica de cada una de las especies conocidas. Sin embargo, es ya necesario realizar estudios genéticos de especiación en los morfos del único veronicélido ampliamente distribuido en Chile central y sur, y en las especies de Orthurethra encontrados en Chile continental y sus islas oceánicas. The content of this paper, part of a series of taxonomic analysis of the land mollusca of Chile being written as a follow up to a synopsis published earlier (Stuardo & Vega 1985), examines the status of the Veronicellidae, Pupillidae and Achatinellidae. Only a few meaningful contributions have been published after the synopsis. So far, two species of Veronicellidae, two species of Pupillidae and 21 species of Achatinellidae have been recorded. Of these, Heterovaginina limayana Lesson with only one record from Chile continues being questioned and the subspecies Pupoides (Ischnopupoides) minimus costatus Biese, is here considered invalid. A full synonymic compilation, with a discussion of morphological distinctive shell traits and topotypic geographical distributions is given for each of these species. However, much needed taxonomic work on the genetic of speciation becomes necessary for the understanding of the morphs of the only widely distributed veronicellid species in central and south Chile and the species of Orthurethra found in continental Chile and the Oceanic Islands
The Complete Mitochondrial Genome of Galba pervia (Gastropoda: Mollusca), an Intermediate Host Snail of Fasciola spp  [PDF]
Guo-Hua Liu, Shu-Yan Wang, Wei-Yi Huang, Guang-Hui Zhao, Shu-Jun Wei, Hui-Qun Song, Min-Jun Xu, Rui-Qing Lin, Dong-Hui Zhou, Xing-Quan Zhu
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0042172
Abstract: Complete mitochondrial (mt) genomes and the gene rearrangements are increasingly used as molecular markers for investigating phylogenetic relationships. Contributing to the complete mt genomes of Gastropoda, especially Pulmonata, we determined the mt genome of the freshwater snail Galba pervia, which is an important intermediate host for Fasciola spp. in China. The complete mt genome of G. pervia is 13,768 bp in length. Its genome is circular, and consists of 37 genes, including 13 genes for proteins, 2 genes for rRNA, 22 genes for tRNA. The mt gene order of G. pervia showed novel arrangement (tRNA-His, tRNA-Gly and tRNA-Tyr change positions and directions) when compared with mt genomes of Pulmonata species sequenced to date, indicating divergence among different species within the Pulmonata. A total of 3655 amino acids were deduced to encode 13 protein genes. The most frequently used amino acid is Leu (15.05%), followed by Phe (11.24%), Ser (10.76%) and IIe (8.346%). Phylogenetic analyses using the concatenated amino acid sequences of the 13 protein-coding genes, with three different computational algorithms (maximum parsimony, maximum likelihood and Bayesian analysis), all revealed that the families Lymnaeidae and Planorbidae are closely related two snail families, consistent with previous classifications based on morphological and molecular studies. The complete mt genome sequence of G. pervia showed a novel gene arrangement and it represents the first sequenced high quality mt genome of the family Lymnaeidae. These novel mtDNA data provide additional genetic markers for studying the epidemiology, population genetics and phylogeographics of freshwater snails, as well as for understanding interplay between the intermediate snail hosts and the intra-mollusca stages of Fasciola spp..
Bridging gaps in the molecular phylogeny of the Lymnaeidae (Gastropoda: Pulmonata), vectors of Fascioliasis
Ana C Correa, Juan S Escobar, Patrick Durand, Fran?ois Renaud, Patrice David, Philippe Jarne, Jean-Pierre Pointier, Sylvie Hurtrez-Boussès
BMC Evolutionary Biology , 2010, DOI: 10.1186/1471-2148-10-381
Abstract: Our phylogenetic analysis demonstrates the existence of three deep clades of Lymnaeidae representing the main geographic origin of species (America, Eurasia and the Indo-Pacific region). This phylogeny allowed us to discuss on potential biological invasions and map important characters, such as, the susceptibility to infection by Fasciola hepatica and F. gigantica, and the haploid number of chromosomes (n). We found that intermediate hosts of F. gigantica cluster within one deep clade, while intermediate hosts of F. hepatica are widely spread across the phylogeny. In addition, chromosome number seems to have evolved from n = 18 to n = 17 and n = 16.Our study contributes to deepen our understanding of Lymnaeidae phylogeny by both sampling at worldwide scale and combining information from various genes (supermatrix approach). This phylogeny provides insights into the evolutionary relationships among genera and species and demonstrates that the nomenclature of most genera in the Lymnaeidae does not reflect evolutionary relationships. This study highlights the importance of performing basic studies in systematics to guide epidemiological control programs.Basommatophora (Gastropoda: Pulmonata) is a suborder comprising essentially all pulmonate gastropods living in freshwater. Basommatophorans are monophyletic and encompass five families: Acroloxidae, Chilinidae, Lymnaeidae, Physidae, and Planorbidae (including the Ancylidae) [1]. The group contains ~300 species and has been extensively studied because some species have a role in transmitting parasites of human and veterinary importance (e.g., Schistosoma and Fasciola). The Lymnaeidae, Physidae and Planorbidae comprise ~90% of the Basommatophoran species [1,2]. The phylogenetic relationships within the Physidae and Planorbidae are now well established (e.g., [3-5]). However, the phylogeny of the Lymnaeidae has only been partially inferred [6-11] and we currently lack a comprehensive treatment of this family.Lymnaeidae sna
New species of Thaumastus from Lagoa Santa region, Minas Gerais State, Brazil (Mollusca, Gastropoda, Pulmonata, Bulimuloidea)
Pena, Meire Silva;Salgado, Norma Campos;Coelho, Arnaldo C. dos Santos;
Iheringia. Série Zoologia , 2005, DOI: 10.1590/S0073-47212005000100004
Abstract: a new species of thaumastus (thaumastus) martens, 1860, from minas gerais state, brazil, is described and illustrated, based on the morphology of the shell, jaw, radula and soft parts.
Nova espécie de Thaumastus da Floresta Atlantica do Paraná, Brasil (Mollusca, Gastropoda, Pulmonata, Bulimuloidea)
Colley, Eduardo;
Iheringia. Série Zoologia , 2012, DOI: 10.1590/S0073-47212012000100006
Abstract: thaumastus straubei sp. nov. is described from atlantic forest of state of paraná, brazil. the generic attribution came from morphological analysis of the shell, radula, jaw and soft parts showing unique and exclusive features that allow distinction from all others species of genus known so far.
Aspectos histológicos das g?nadas hermafroditas de Biomphalaria glabrata e Bradybaena similaris (Mollusca, Gastropoda, Pulmonata)
Silva, Rinaldo Florêncio da;Cubas, Jairo José Matozinho;Moraes, Josué de;
Papéis Avulsos de Zoologia (S?o Paulo) , 2009, DOI: 10.1590/S0031-10492009003300001
Abstract: biomphalaria glabrata (say, 1818) is a freshwater pulmonate gastropod that represents great medical importance. bradybaena similaris (férussac, 1821) is a terrestrial pulmonate gastropod and an important plague to the different plant cultures with economic interest. both species are intermediate hosts of helminths. these molluscs have hermaphrodites gonads producing eggs and sperm. here, we examined histoformological aspects of hermaphrodites gonads of both b. glabrata and b. similaris. the gonad of b. similaris is subdivided into lobes and presence of glands in its interior, which was not observed in b. glabrata. moreover, in b. similaris the germ cells are accumulated in some areas, and has one oocyte in each follicle in the gonad; however, in b. glabrata the germ cells are juxtaposed and more than one oocyte in each follicle.
Moluscos de importancia econ?mica no Brasil: II Subulinidae, Subulina octona (Bruguiére) (Mollusca, Gastropoda, Pulmonata, Stylommatophora)
Araújo, José Luiz de B.;Bessa, Elizabeth Cristina de A.;
Revista Brasileira de Zoologia , 1993, DOI: 10.1590/S0101-81751993000300016
Abstract: a study of the anatomy of subulina octona, mainly the genital and digestive systems, was undertaken in order to obtain additional data on the taxonomic position in the genus subulina. the importance of the species as intermediate host for several helminths which occur in brazil was also discussed.
Moluscos de importancia econ?mica no Brasil: III. Subulinidae, Leptinaria unilamellata (Orbigny) (Mollusca, Gastropoda, Pulmonata, Stylommatophora)
Araújo, José Luiz de B.;Keller, Darli Grativol;
Revista Brasileira de Zoologia , 1993, DOI: 10.1590/S0101-81751993000300017
Abstract: an anatomic study of leptinaria unilamellata (orbigny, 1835) was made emphasizing the genital system, the pallial chamber the radulae and the mandible. the details of these parts characterize better the species and allow more systematic clarity to the group. the importance of the evolutive cycle of the two trematodes, postharmostomum gallinum (witenberg, 1923) and paratanaisia bragai (santos, 1934) both parasites of domestic birds in brazil is accentuated.
Redescri??o dos tipos de Veronicellidae (Mollusca, Gastropoda) neotropicais: X. Os tipos de Diplosolenodes occidentalis (Guilding, 1825) no British Museum (Natural History), Londres
Thomé, José Willibaldo;
Revista Brasileira de Zoologia , 1984, DOI: 10.1590/S0101-81751984000200015
Abstract: diplosolenodes occidentalis (guilding, 1825) (mollusca, gastropoda, veronicellidae) is redescribed upon the examination of types in the british museum (natural history). new characters of external and internal morphohgy are described. a leclotype, is selected.
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