Search results for "Introduced species"
showing 10 items of 147 documents
Differential influence of Pomphorhynchus laevis (Acanthocephala) on brain serotonergic activity in two congeneric host species.
2007
The physiological mechanisms by which parasites with complex life cycles manipulate the behaviour of their intermediate hosts are still poorly understood. In Burgundy, eastern France, the acanthocephalan parasitePomphorhynchus laevisinverses reaction to light in its amphipod hostGammarus pulex, but not inGammarus roeseli, a recent invasive species. Here, we show that this difference in manipulation actually reflects a difference in the ability of the parasite to alter brain serotonergic (5-HT) activity of the two host species. Injection of 5-HT in uninfected individuals of both host species was sufficient to inverse reaction to light. However, a difference in brain 5-HT immunocytochemical s…
Competition among introduced and indigenous submerged macrophytes in a southern mediterranean shallow system
2011
In Termini Imerese H. stipulacea has been recorded inside artificial basins, located near the harbour, built arranging breakwater barriers along the coast in order to protect the coastal road. From July until the beginning of November the seagrass formed beds with cover values ranging from 70% to 80%, and it was in contact either with the seagrass Cymodocea nodosa (Ucria) Ascherson (cover values of 20-25%) or the green alga Caulerpa prolifera (Forsskål) Lamouroux (cover values of 10-15%). H. stipulacea in good health conditions showed a clear competition strategy with C. nodosa as proved by registered cover values. But during natural denudations occurring in winter, C. racemosa var. cylindr…
Successive Invasion-Mediated Interspecific Hybridizations and Population Structure in the Endangered Cichlid Oreochromis mossambicus.
2013
Hybridization between invasive and native species accounts among the major and pernicious threats to biodiversity. The Mozambique tilapia Oreochromis mossambicus, a widely used freshwater aquaculture species, is especially imperiled by this phenomenon since it is recognized by the IUCN as an endangered taxon due to genetic admixture with O. niloticus an invasive congeneric species. The Lower Limpopo and the intermittent Changane River (Mozambique) drain large wetlands of potentially great importance for conservation of O. mossambicus, but their populations have remained unstudied until today. Therefore we aimed (1) to estimate the autochthonous diversity and population structure among genet…
Sublethal Pyrethroid Insecticide Exposure Carries Positive Fitness Effects Over Generations in a Pest Insect
2019
AbstractStress tolerance and adaptation to stress are known to facilitate species invasions. Many invasive species are also pests and insecticides are used to control them, which could shape their overall tolerance to stress. It is well-known that heavy insecticide usage leads to selection of resistant genotypes but less is known about potential effects of mild sublethal insecticide usage. We studied whether stressful, sublethal pyrethroid insecticide exposure has within-generational and/or maternal transgenerational effects on fitness-related traits in the Colorado potato beetle (Leptinotarsa decemlineata) and whether maternal insecticide exposure affects insecticide tolerance of offspring…
No evidence of DUI in the Mediterranean alien species Brachidontes pharaonis (P. Fisher, 1870) despite mitochondrial heteroplasmy
2022
AbstractTwo genetically different mitochondrial haplogroups of Brachidontes pharaonis (p-distance 6.8%) have been identified in the Mediterranean Sea. This hinted at a possible presence of doubly uniparental inheritance in this species. To ascertain this possibility, we sequenced two complete mitogenomes of Brachidontes pharaonis mussels and performed a qPCR analysis to measure the relative mitogenome copy numbers of both mtDNAs. Despite the presence of two very similar regions composed entirely of repetitive sequences in the two haplogroups, no recombination between mitogenomes was detected. In heteroplasmic individuals, both mitogenomes were present in the generative tissues of both sexes…
Avian mite dermatitis: an Italian case indicating the establishment and spread of Ornithonyssus bursa (Acari: Gamasida: Macronyssidae) (Berlese, 1888…
2015
Background Avian mite dermatitis is a skin disease caused in mammals by the incidental bites of blood-sucking mites which customarily parasitize wild and domestic birds. It manifests in the form of pruritic, erythematous, or urticarial papules, with a central sting mark, in skin regions normally covered by clothing. The species mainly implicated in human bite cases are Dermanyssus gallinae, Ornithonyssus sylviarum and, less frequently, Ornithonyssus bursa. The latter is mainly a tropical and subtropical mite and its – presumably transitory – presence has been recorded only once in Europe, in migratory birds. Case report We report a case of avian mite dermatitis in a 70-year-old man, an owne…
A co-invasive microsporidian parasite that reduces the predatory behaviour of its host Dikerogammarus villosus (Crustacea, Amphipoda).
2014
SUMMARYParasites are known to affect the predatory behaviour or diet of their hosts. In relation to biological invasions, parasites may significantly influence the invasiveness of the host population and/or mediate the relationships between the invader and the invaded community. Dikerogammarus villosus, a recently introduced species, has had a major impact in European rivers. Notably, its high position in trophic web and high predatory behaviour, have both facilitated its invasive success, and affected other macroinvertebrate taxa in colonized habitats. The intracellular parasite Cucumispora dikerogammari, specific to D. villosus, has successfully dispersed together with this amphipod. Data…
The first colonization of the Genus Amphistegina and other exotic benthic foraminifera of the Pelagian Islands and south-eastern Sicily (central Medi…
2014
Abstract A detailed study of the marine sediments collected on the inner shelf of some of the selected areas of the central Mediterranean Sea has been carried out in order to verify the presence of exotic benthic foraminiferal species. Since 2000, the coastal marine environments of the Pelagian Islands and of Sicily (central Mediterranean) have been increasingly colonized by exotic species (i.e. fishes and algae) originating both from the Atlantic Ocean and the Red Sea. The studied areas (Pelagian Islands and SE Sicily) are located in the middle of the Mediterranean Sea. Therefore, they represent an ideal place to understand how exotic species, coming from different Oceans, may have coloniz…
Monitoring of alien aquatic plants in the inland waters of Sicily (Italy)
2020
Updated and reliable data on the presence and distribution of alien aquatic plant species in Sicily are lacking, and there is a need to fill this gap for a proper and efficient management of freshwater ecosystems and biodiversity. This paper reviews the available knowledge about alien aquatic vascular plants in the inland waters of Sicily (Italy). The aim is to provide an updated checklist, as a first step in the study of the impact of those plants on the native species and ecosystems of this Mediterranean island. The paper focuses on the strictly aquatic species (hydrophytes), excluding emergent macrophytes. Four species were listed, all of them free-floating and with American origin. Most…
Diversity and Distribution of the Dinoflagellates Brachidinium, Asterodinium and Microceratium (Brachidiniales, Dinophyceae) in the open Mediterranea…
2011
Diversity and Distribution of the DinoflagellatesBrachidinium, AsterodiniumandMicroceratium(Brachidiniales, Dinophyceae) in the open Mediterranean SeaBrachidiniacean dinoflagellates have been investigated in the open waters of the Mediterranean Sea, along a transect from the south of France to the south of Cyprus (20 June-18 July 2008).BrachidiniumandKarenia papilionaceaoften co-occurred,B. capitatumpredominating in the surface waters. The highest abundance ofBrachidiniumwere found in the upper 25min the western Mediterranean with amaximum (24 cells L-1) at a depth of 5 m in the Balearic Sea.Asterodinium(up to 4 cells L-1) was recorded below of deep chlorophyll maxima. The genusMicroceratiu…