Search results for " Brachidontes"

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…

Heart beat rate of invasive Brachidontes pharaonis with respect to the native Mytilaster minimus within the Mediterranean Sea at varying salinites

2011

Changes in heart beat rates (HBR) of Brachidontes pharaonis (an invasive Lessepsian species) and Mytilaster minimus (a native Mediterranean species) in response to changes in salinity values from brackish (20) to extreme hyper-saline (75) were investigated both in situ and in the laboratory. The two species displayed different responses to varying salinity, with clear differences in HBR observed between groups investigated at different salinities and between groups originating from different environments. The native species, adapted to narrow salinity changes as those observed in the superficial waters of the Mediterranean Sea, showed signs of stress at salinities slightly above 37 (in the …

Eco-physiological response of two marine bivalves to acute exposition to commercial Bt-based pesticide

2013

Microbial products based on the entomopathogenic bacterium Bacillus thuringiensis (Bt) are among the most common biopesticides used worldwide to suppress insect pests in forests, horticulture and agricultural crops. Some of the effects of commercial Bt have been recorded for terrestrial and freshwater non-target organisms but little research is available on marine fauna. Nevertheless, due to the contiguity of agro-ecosystems and coastal habitats, marine fauna may be highly influenced by this control method. We studied the effect of a commercial Bt product on the physiological and ecological responses and the energy budget of two of the most frequent marine intertidal bivalves in the Mediter…

Morphometric diversity of the mussel Brachidontes pharaonis in different coastal environments

2010

In the debate on how and why biodiversity evolves spatially and temporally and in an attempt to assess the further effects of anthropogenic activities, the ability of marine invertebrate to express a large spectrum of phenotypical plasticity can have a central role. The ability of a single genotype to produce more than one alternative form of morphology and/or physiological state should be larger in species living in highly changing waters like shallow habitats. Invertebrates, there, usually experience ample changes of temperature and food availability on annual, seasonal, diurnal and hourly bases which are the two main drivers leading the life histories of these organisms. In such circumst…

Effect of salinity and temperature on feeding physiology and scope for growth of an invasive species (Brachidontes pharaonis - MOLLUSCA: BIVALVIA) wi…

2008

Abstract The Indo-Pacific mytilid Brachidontes pharaonis (Bivalvia, Fischer 1870) offers an excellent model for the study of “Lessepsian migration” and the successive colonization at new Mediterranean locations. This species in out competing indigenous bivalves is particularly well adapted to Mediterranean conditions and this is likely due to biological characteristics and physio-ecological plasticity. In the present paper, we report on clearance rate (CR), respiration rate (RR) and Scope for Growth (SFG) of B. pharaonis collected from a Western Sicilian pond (Southern Tyrrhenian, MED). Physiological variables were determined in response to a range of temperatures from 11 ° to 20 °C and a b…

Parameterisation of bivalve functional traits for mechanistic eco-physiological dynamic energy budget (DEB) models

2013

Mechanistic models such as those based on dynamic energy budget (DEB) theory are emergent ecomechanics tools to investigate the extent of fitness in organisms through changes in life history traits as explained by bioenergetic principles. The rapid growth in interest around this approach originates from the mechanistic characteristics of DEB, which are based on a number of rules dictating the use of mass and energy flow through organisms. One apparent bottleneck in DEB applications comes from the estimations of DEB parameters which are based on mathematical and statistical methods (covariation method). The parameterisation process begins with the knowledge of some functional traits of a tar…

Discriminazione di presunte specie criptiche: un approccio di morfometria geometrica in Brachidontes pharaonis-variabilis (Bivalvia, Mytilidae).

2010

Scope for Growth of the intertidal Lessepsian bivalve Brachidontes pharaonis (Fischer 1870) at varying environmental variables

2009

The concept of energy available to organismal growth (i.e. scope for growth; SFG) assumes a central role in studying the behaviour of successful invaders in aquatic habitats: the higher the energy allocated to growth and reproduction, the greater the likelihood of stability/persistence in space over time of aquatic populations. When successful invaders find useful life conditions (i.e., allowing to reach maximum SFG), they compete for space and resources with indigenous species, altering the functioning of entire ecosystems. The Indo-Pacific bivalve Brachidontes pharaonis offers an excellent model for the study of “Lessepsian migration” and the successive colonization at new Mediterranean l…