Risk of invasion and disease transmission by the Australasian freshwater snail Orientogalba viridis (Lymnaeidae): a field and experimental study.

Background: Biological invasions pose risks to the normal functioning of ecosystems by altering the structure and composition of several communities. Molluscs stand out as an extensively studied group given their long history of introduction by either natural or anthropogenic dispersal events. An alien population of the lymnaeid species Orientogalba viridis was first sighted in 2009 in southern Spain.

Molecular Identification of the Human Pathogen Amphimerus sp. in the Freshwater Snail Aroapyrgus sp. in Ecuador.

Here, we report for the first time the snail intermediate host for the Amphimerus liver fluke, a foodborne trematodiasis. In Ecuador, Amphimerus of the Opisthorchiidae family, infects humans, cats, and dogs, in the tropical Pacific-coast region. Opisthorchiidae comprising also Clonorchis sinensis, Opisthorchis sp.

Prevalence of Fasciola hepatica infection in Galba cousini and Galba schirazensis from an Andean region of Ecuador.

Some Lymnaeid snails are intermediate hosts of the liver fluke Fasciola hepatica, the causal agent of fasciolosis, a zoonotic parasitic disease. Human and livestock fasciolosis has been reported in a highland community located in the Chimborazo Province of the Ecuadorian Andes. However, no previous study has been carried out to identify which snail species act as intermediate host/s of F.

Lymnaeidae from Santander and bordering departments of Colombia: Morphological characterization, molecular identification and natural infection with Fasciola hepatica.

The Lymnaeidae constitute a family of freshwater gastropod molluscs whose diversity and ecology have been infrequently studied throughout Colombia. Some lymnaeid species act as intermediate hosts of trematode parasites, which are of great importance in both the veterinary and medical fields. Among trematode parasites, Fasciola hepatica is best known for being an important parasite of sheep and cattle for decades and causes significant economic losses in these livestock species.

Reviewing Fasciola hepatica transmission in the West Indies and novel perceptions from experimental infections of sympatric vs. allopatric snail/fluke combinations.

Fasciolosis is an important food-borne parasitic disease affecting over two million people worldwide with economic losses related to cattle production of up to US$ 3 billion annually. Despite the long known presence of Fasciola hepatica in the Caribbean islands its transmission is not well known. This study reviews historical and recent data on fasciolosis in the West Indies, revealing for the first time the outcomes of sympatric and allopatric fluke/snail interactions in the area by exploring the susceptibility of four lymnaeid species after exposure to F.

Patterns of distribution, population genetics and ecological requirements of field-occurring resistant and susceptible Pseudosuccinea columella snails to Fasciola hepatica in Cuba.

Pseudosuccinea columella snails transmit the trematode Fasciola hepatica, but in Cuba, six naturally occurring populations successfully resist parasite infection. Here, we present an updated distribution of P. columella in Cuba; 68 positive sites with the earliest records more abundant in west-central Cuba and with east-central populations generally corresponding to the newest samples.

Modeling competition, niche, and coexistence between an invasive and a native species in a two-species metapopulation.

Modeling the dynamics of competition and coexistence between species is crucial to predict long-term impacts of invasive species on their native congeners. However, natural environments are often fragmented and variable in time and space. In such contexts, regional coexistence depends on complex interactions between competition, niche differentiation and stochastic colonization-extinction dynamics.

Bioinvasion Triggers Rapid Evolution of Life Histories in Freshwater Snails.

Biological invasions offer interesting situations for observing how novel interactions between closely related, formerly allopatric species may trigger phenotypic evolution in situ. Assuming that successful invaders are usually filtered to be competitively dominant, invasive and native species may follow different trajectories. Natives may evolve traits that minimize the negative impact of competition, while trait shifts in invasives should mostly reflect expansion dynamics, through selection for colonization ability and transiently enhanced mutation load at the colonization front.

Is Galba schirazensis (Mollusca, Gastropoda) an intermediate host of Fasciola hepatica (Trematoda, Digenea) in Ecuador?

Fasciolosis is a widely distributed disease in livestock in South America but knowledge about the epidemiology and the intermediate hosts is relatively scarce in Ecuador. For three months, lymnaeid snails were sampled (n = 1482) in Pichincha Province at two sites located in a highly endemic area. Snails were identified (based on morphology and ITS-2 sequences) and the infection status was established through microscopic dissection and a multiplex polymerase chain reaction (PCR)-based technique.

Natural prevalence in Cuban populations of the lymnaeid snail Galba cubensis infected with the liver fluke Fasciola hepatica: small values do matter.

Natural infections of lymnaeid snails by Fasciola hepatica are of primary importance to study transmission. Also, infected snails in the field can be used to explore the existing compatibility in host-parasite interactions. This paper aimed to describe the infection rate of Galba cubensis populations in fasciolosis transmission areas.

Lymnaea cubensis, an experimental intermediate host for Fascioloides magna.

Single-miracidium infections of Lymnaea cubensis (Pfeiffer) from Guadeloupe with the giant liver fluke Fascioloides magna (Bassi, 1875) (Digenea) were carried out during five successive snail generations to determine if this lymnaeid might sustain complete larval development of the parasite. Controls were constituted by a French population of Galba truncatula (Miller) (a single generation) infected according to the same protocol. It was recorded that prevalence and intensity of F.

Metapopulation dynamics of species with cryptic life stages.

Quantifying metapopulation dynamics is a challenging task. Difficulties particularly arise in species that possess unobservable resistance forms that bias the estimation of colonization and persistence rates. Here, we develop a general multistate occupancy model that allows estimation of species persistence for both normal and resistant forms, even when the latter are not detectable.

Morphological and molecular characterization of Neotropic Lymnaeidae (Gastropoda: Lymnaeoidea), vectors of fasciolosis.

Lymnaeidae play a crucial role in the transmission of fasciolosis, a disease of medical and veterinary importance. In the Neotropic, a region where fasciolosis is emergent, eight Lymnaeidae species are currently considered valid. However, our knowledge of the diversity of this taxon is hindered by the fact that lymnaeids exhibit extremely homogeneous anatomical traits.

Bridging gaps in the molecular phylogeny of the Lymnaeidae (Gastropoda: Pulmonata), vectors of Fascioliasis.

Background: Lymnaeidae snails play a prominent role in the transmission of helminths, mainly trematodes of medical and veterinary importance (e.g., Fasciola liver flukes).

Immunoblot analysis of membrane antigens of Schistosoma mansoni, Schistosoma intercalatum, and Schistosoma haematobium against Schistosoma-infected patient sera.

Antigens present in aqueous n-butanolic extracts (BE) of Schistosoma mansoni (Venezuelan JL strain), Schistosoma intercalatum (Cameroon EDEA strain), and Schistosoma haematobium (Yemen strain) adult worm membranes were compared in immunoblot against sera of patients infected with S. mansoni, S. intercalatum, S.

Excretory-secretory products of larval Fasciola hepatica investigated using a two-dimensional proteomic approach.

So far, very few secreted proteins from trematodes have been characterized, although their role in the mechanisms that allow the parasite to escape host's immune response have been largely documented. Here we performed a proteomic analysis of excretory-secretory proteins from the intra-molluscan larval stages of Fasciola hepatica. We identified two antioxidative enzymes: a Cu/Zn-superoxide dismutase (Cu/Zn SOD) and a thioredoxin (TRX) previously characterized in ES products from adult stages.

High genetic variance in life-history strategies within invasive populations by way of multiple introductions.

Biological invasions represent major threats to biodiversity as well as large-scale evolutionary experiments. Invasive populations have provided some of the best known examples of contemporary evolution [3-6], challenging the classical view that invasive species are genetically depauperate because of founder effects. Yet the origin of trait genetic variance in invasive populations largely remains a mystery, precluding a clear understanding of how evolution proceeds.

Pseudosuccinea columella (Say 1817) (Gastropoda, Lymnaeidae), snail host of Fasciola hepatica: first record for France in the wild.

The lymnaeid snail Pseudosuccinea columella has shown strong invasive capabilities in the last decades, and this species has now a worldwide distribution. So far, the presence of this snail in Europe was restricted to botanical gardens, but the recent discovery of a few specimens along the banks of the Lot River, southwestern France is the first record of this species in the wild. The first generation of this P.

Amassing diversity in an ancient lake: evolution of a morphologically diverse parthenogenetic gastropod assemblage in Lake Malawi.

Exceptional ecological niche diversity, clear waters and unique divergent selection pressures have often been invoked to explain high morphological and genetic diversity of taxa within ancient lakes. However, it is possible that in some ancient lake taxa high diversity has arisen because these historically stable environments have allowed accumulation of lineages over evolutionary timescales, a process impossible in neighbouring aquatic habitats undergoing desiccation and reflooding. Here we examined the evolution of a unique morphologically diverse assemblage of thiarid gastropods belonging to the Melanoides polymorpha'complex' in Lake Malawi.

Dispersal in a parasitic worm and its two hosts: consequence for local adaptation.

Characterizing host and parasite population genetic structure and estimating gene flow among populations is essential for understanding coevolutionary interactions between hosts and parasites. We examined the population genetic structure of the trematode Schistosoma mansoni and its two host species (the definitive host Rattus rattus and the intermediate host Biomphalaria glabrata) using microsatellite markers. Parasites were sampled from rats.

Detection and genetic distance of resistant populations of Pseudosuccinea columella (Mollusca: Lymnaeidae) to Fasciola hepatica (Trematoda: Digenea) using RAPD markers.

Twelve natural populations of Pseudosuccinea columella snails, sampled in the western and central regions of Cuba, were analyzed using the RAPD-PCR technique to screen for resistance to Fasciola hepatica. Ten OPA primers previously shown to produce marker bands for resistance and susceptibility were tested. A new population of P.

Camouflaged invasion of Lake Malawi by an Oriental gastropod.

In this study we report the first animal invasion, to our knowledge, into Lake Malawi. The colonizer is a non-native morph of the gastropod Melanoides tuberculata that differs substantially in external shell characters from co-occurring indigenous forms. However, because the species possesses extensive within-Africa geographical variation in shell morphology, it was unclear whether the invasion was range expansion of a native African morph, or a colonization from elsewhere.