Search results for "Brachidontes pharaonis"
showing 10 items of 24 documents
Functional and energetic consequences of climate change on a predatory whelk
2017
Abstract The increasing rise in sea surface temperature caused by human activities currently represents the major threat to biodiversity and natural food webs. In this study we used the Lessepsian mussel Brachidontes pharaonis, one of the most recent invaders of the Mediterranean Sea, as a model to investigate the effect of a novel prey and a chronic increase in temperatures on functional parameters of local consumers, compared to the native mytilid species Mytilaster minimus. In particular we focused on the whelk Stramonita haemastoma, a widespread Mediterranean intertidal predator that actively preys on bivalves, barnacles and limpets, by studying the direct effects of such multiple stres…
Silver Nanoparticles Affect Functional Bioenergetic Traits in the Invasive Red Sea Mussel Brachidontes pharaonis
2016
We investigated the functional trait responses to 5 nm metallic silver nanoparticle (AgNPs) exposure in the Lessepsian-entry bivalveB. pharaonis. Respiration rate (oxygen consumption), heartbeat rate, and absorption efficiency were evaluated across an 8-day exposure period in mesocosmal conditions. Basal reference values from not-exposed specimens were statistically compared with those obtained from animals treated with three sublethal nanoparticle concentrations (2 μg L−1, 20 μg L−1, and 40 μg L−1). Our data showed statistically significant effects on the average respiration rate ofB. pharaonis. Moreover, complex nonlinear dynamics were observed as a function of the concentration level and…
Local consumers are the first line to control biological invasions: a case of study with the whelk Stramonita haemastoma (Gastropoda: Muricidae)
2016
The increasing spread of invasive species in the Mediterranean Sea determines several alterations in local food webs, changing the feeding habits of native organisms. The whelk Stramonita haemastoma is a widespread Mediterranean gastropod that consumes bivalves, barnacles and limpets. Previous studies showed a shift in its diet from the bivalve Mytilaster minimus to the invasive mussel Brachidontes pharaonis, presumably due to a higher energy gain. Here we tested whelks’ preference among natives and a novel prey, calculating the profitability ratio, and integrating those results with biochemical analysis on prey tissues and the routine metabolism of the whelks. Further, we used the scaled f…
Population structure of Brachidontes pharaonis (P. Fisher, 1870) (Bivalvia, Mytilidae) in the Mediterranean Sea, and evolution of a novel mtDNA polym…
2006
Abstract Brachidontes pharaonis (Fisher P, 1870) is an Indo-Pacific mussel that has colonized the Mediterranean Sea via the Suez Canal. Mussels may have migrated by natural dispersal of pelagic larvae, or they may have been transported on the hulls of ships, or in ballast water, or by some combination of these. Mitochondrial COI sequences (618 bp) from 101 mussels from six localities in the central and eastern Mediterranean Sea and from one site in the Red Sea were used to describe population structure. Analysis of molecular variance indicated that frequencies differed among populations, and that 92% of the variation resided within populations. The majority of haplotypes were private allele…
Functional consequences of prey acclimation to ocean acidification for the prey and its predator
2016
Ocean acidification is the suite of chemical changes to the carbonate system of seawater as a consequence of anthropogenic carbon dioxide (CO2) emissions. Despite a growing body of evidences demonstrating the negative effects of ocean acidification on marine species, the consequences at the ecosystem level are still unclear. One factor limiting our ability to upscale from species to ecosystem is the poor mechanistic understanding of the functional consequences of the observed effects on organisms. This is particularly true in the context of species interactions. The aim of this work was to investigate the functional consequence of the exposure of a prey (the mussel Brachidontes pharaonis) t…
Filogenesi e Filogeografia del Sistema Brachidontes pharaonis-variabilis (Bivalvia, Mytiloida, Mytilidae)
2012
Cytogenetic characterization ofBrachidontes pharaonis(Fisher P., 1870): Karyotype, banding and fluorescentin situhybridization (fish) (Mollusca: Biva…
2000
Abstract The mussel Brachidontes pharaonis (Fisher P., 1870) (Bivalvia: Mytilidae) has a diploid chromosomal set of 28 made up of 14 pairs of which eight are mono-armed (ST) and six bi-armed (M+SM). Fourteen bivalents occur in spermatocytes both at pachytene and metaphase-I. The use of combined silver and CMA3 staining reveals that nucleolus organizer regions (NORs) are located terminally on the long arm of a small subtelocentric chromosome pair (pair 14) and are compartmentalized in GC base pairs. A Paracentrotus lividus (Echinodermata) 4.3 kilobase (kb) rDNA probe (prR14) consisting of sequences from the 3′ end of 18S rDNA to the 3′ end of 26S rDNA was used to map the rDNA loci of B. phar…
Identification, cloning and environmental factors modulation of a αβ defensin from the lessepsian invasive mussel Brachidontes pharaonis (Bivalvia: M…
2015
International audience; Immunological effectors of invasive species playing a role in addressing new colonization are still poorly studied. In the present study the cDNA sequence of the defensin from a Lessepsian invasive species, the Red Sea mussel Brachidontes pharaonis, was cloned using RACE method. Defensins are a class of widely known antimicrobial peptides (AMPs), oligopeptides with a broad spectrum of targeted organisms ranging from viruses to parasites. Analysis of BpDef sequence (262 bp) revealed the presence of an ORF coding for 81 amino acids. The full-length amino acid sequence showed the highest similarity to antimicrobial peptides MGD1 and MGD2 sequence from Mytilus galloprovi…
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…
A new lessepsian species in the western Mediterranean ( Brachidontes pharaonis Bivalvia: Mytilidae): density, resource allocation and biomass
2008
The present study reports on population dynamics and growth performance relative to a lesser known exotic invasive species ( Brachidontes pharaonis ) inhabiting the southern Mediterranean. The study was carried out in western Sicily, where B. pharaonis is present on both the submerged and emerged surfaces of a hyperhaline saltpan. Individuals were scraped, counted and measured for shell length, total weight, somatic, gonadic and shell biomass. Brachidontes pharaonis intensively colonized all hard substrates of the saltpan with annual average densities of 375 ± 293 ind. 400 cm −2 with density peaks in autumn as a function of habitat. The occurrence of juveniles was different for mediolittora…