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Inproceedings Reference Characterization of the colonizing Decollate Snail, Rumina decollata (Mollusca: Pulmonata: Stylommatophora)
The hermaphroditic, facultatively selfing, land snail Rumina decollata is a common, widespread species indigenous in the western Mediterranean region, that has been introduced in many other parts of the world. Recent DNA sequence analyses have shown that R. decollata is a complex of several (phylogenetic) species, two of them corresponding to previously distinguished allozyme strains with different body colours (light vs. dark). Therefore, considering this new taxonomic interpretation, we here attempt to identify which, and how many, species of the R. decollata complex have been introduced outside their native area. Comparative DNA sequence analysis of introduced populations from South America, North America, Japan and the North Atlantic Islands vs. native populations from the Mediterranean area, revealed that all introduced populations belong to one single phylogenetic species, previously recognized as the dark strain. Therefore, the colonizing and invasive character of R. decollata is mainly, if not entirely, due to this dark strain. Furthermore, the Iberian Peninsula seems to be an important source for introduced R. decollata populations outside Europe. Within this work, we will discuss about the invasive character of the dark strain and the possible source areas of the introduced populations.
Located in Library / RBINS Staff Publications
Inproceedings Reference Contemporary population genetic differentiation in Melarhaphe neritoides (Gastropoda: Littorinidae), a long-lived planktonic-dispersing mollusc
Marine invertebrates with planktonic-dispersing larvae are assumed to be good dispersers over long distances. This high dispersal capacity implies a high gene flow between populations and a homogeneous population genetic structuring over wide geographic scales. The marine gastropod Melarhaphe neritoides has a long-lived planktonic larval dispersal stage and allozyme data suggest that it is genetically homogeneous over its whole European distribution area. By contrast, prelimi-nary mtDNA sequence data uncovered a remarkable degree of genetic diversity and genetic structuring on smaller geo-graphic scales. In order to explore this mtDNA diversity and structuring in M. neritoides, we started to survey sequence vari-ation at COI and 16S rDNA all over the Azores archipelago. These data reveal that the Azorean populations share very few haplotypes. Hence, it seems that M. neritoides with its long-lived planktonic larval stage nevertheless shows a strong local population genetic structuring and thus challenges the current paradigm that correlates modes of larval development with levels of genetic structuring. It also stresses the importance of the sampling intensity (both in terms of numbers of speci-mens and genetic markers) to avoid experimental biases when assessing genetic diversity. An
Located in Library / RBINS Staff Publications
Inproceedings Reference Characterization of the colonising Decollate Snail, Rumina decollata (Mollusca: Pulmonata: Stylommatophora)
Located in Library / RBINS Staff Publications
Inproceedings Reference Microsatellite markers for analysis of parentage and sexual behavior of banana slugs (Pulmonata: Arionidae: Ariolimax)
Terrestrial pulmonate slugs are hermaphroditic and often are capable of both outcrossing and self-fertilization. This mixed breeding system may severely affect population genetic structuring and taxonomic differentiation. Currently little is known about the breeding system(s) of Banana slugs (Ariolimax), a group of taxonomically ill-defined slugs living along the West Coast of North America, from California to southern Alaska. Based on genital morphology and mtDNA sequence data (COI, 16S and CytB), the genus Ariolimax is nowadays interpreted as a group of eight species level taxa, viz Ariolimax columbianus, A. buttoni, A. stramineus, A. californicus, A. dolichophallus, A. brachyphallus and two undescribed species. These species ap-pear to be closely related as 19 microsatellite DNA loci identified from A. californicus consistently amplify in all of the de-scribed taxa and share many alleles. Hence, these microsatellites can help to clarify Ariolimax taxonomy. To this end, four microsatellite loci were used to study potential interspecific crosses of A. californicus x A. dolichophallus. This showed that none of these crosses produced hybrid offspring and that A. californicus reveals multiple paternity under natural conditions. Conversely, a panel of 28 microsatellites applied to cross-breeding experiment between two populations of A. buttoni, showed that all the parental specimens involved only three homozygous multilocus genotypes (MLG) and that offspring of pairs in which both parents had a different genotype, always were monomorphic for the same homozygous MLG of one of the parents. This confirms that A. buttoni is able to self-fertilize. Yet, to what extent self-fertilization is common in natural condi-tions remains to be investigated.
Located in Library / RBINS Staff Publications
Inproceedings Reference Complex biogeography of cryptic species in the Gyratrix hermaphroditus species complex.
Located in Library / RBINS Staff Publications
Inproceedings Reference The meiofauna paradox unresolved: Cryptic speciation in Gyratrix hermaphroditus (Kalyptorhynchia, Platyhelminthes).
Located in Library / RBINS Staff Publications
Inproceedings Reference There’s more than meets the eye: population structure in the Ceratitis “FAR complex”.
Analyses of mitochondrial and nuclear DNA sequences hitherto failed to resolve the three morphospecies of the so-called Ceratitis “FAR complex” (C. fasciventris, C. anonae, C. rosa). Therefore, we developed a set of microsatellite markers for a first population genetic survey of this species complex. Specimens of C. fasciventris, C. anonae, and C. rosa (27 populations, n=621) collected across their respective distribution ranges were genotyped at 16 polymorphic microsats. Genetic distance analyses distinguished at least five bootstrap supported population groups, each including samples from one of the three morphospecies. The Bayesian assignments implemented in STRUCTURE show that (1) C. rosa is represented by at least two clusters of individuals (R1, R2) that can occur in sympatry/parapatry, but that may have different developmental thresholds, (2) C. fasciventris is represented by at least two, geographically separated, clusters (F1, F2), and (3) C. anonae is genetically more homogeneous and doesn’t show a clear intraspecific structuring (cluster A). The differentiation of the C. rosa and C. fasciventris clusters is supported by morphological differences in the male secondary sexual characters. Genetic divergences between the C. rosa clusters and between the C. fasciventris clusters are comparable to the interspecific divergences among C. fasciventris, C. anonae, and C. rosa. Higher genetic distances were observed between the morphologically similar C. rosa and C. fasciventris, while C. anonae appears as closely related to both F1 and R2. The microsats used in this study thus unmasked a complex, and partly cryptic, population genetic structure within the FAR morphospecies. Keywords: Tephritidae, population genetics, microsats
Located in Library / RBINS Staff Publications
Inproceedings Reference Canine mitochondrial genome sequencing to improve the genetic profiling of dog hair.
Located in Library / RBINS Staff Publications
Inproceedings Reference Rapid divergence in morphology, physiology and behaviour among island populations of lizards.
Located in Library / RBINS Staff Publications
Inproceedings Reference Population genetic differentiation in Melarhaphe neritoides, a marine gastropod with a long-lived planktonic larval stage.
Marine invertebrates with planktonic-dispersing larvae are assumed to be good dispersers over long distances. This high dispersal capacity implies a high gene flow between populations and a homogeneous population genetic structuring over wide geographic scales. The marine gastropod Melarhaphe neritoides has a long-lived planktonic larval dispersal stage and allozyme data suggest that it is genetically homogeneous over its whole European distribution area. In contrast, preliminary mtDNA sequence data uncovered a remarkable degree of genetic diversity and genetic structuring on smaller geographic scales. In order to explore this mtDNA diversity and structuring in M. neritoides we started to survey sequence variation at COI and 16S rDNA all over the Azores archipelago. These data reveal that the Azorean populations share very few haplotypes, both between and within islands. Hence, it seems that M. neritoides with its long-lived planktonic larval stage nevertheless shows a strong local population genetic structuring and thus challenges the current paradigm that correlates modes of larval development with levels of genetic structuring. It also stresses the importance of the sampling intensity (both in terms of numbers of specimens and genetic markers) to avoid experimental biases when assessing genetic diversity.
Located in Library / RBINS Staff Publications