36 research outputs found
First record of the Atlantic blue crab Callinectes sapidus (Crustacea: Brachyura: Portunidae) in the Segura River mouth (Spain, southwestern Mediterranean Sea)
A single male individual of Callinectes sapidus (Crustacea, Decapoda, Portunidae) was collected on 6 December 2014 in the Segura River mouth in southeastern Spain. Information on collection site, DNA barcoding, and its present distribution and dispersal strategies are provided
Genetic diversity and connectivity remain high in Holothuria polii (Delle Chiaje 1823) across a coastal lagoon-open sea environmental gradient
Coastal lagoons represent habitats with widely heterogeneous environmental conditions, particularly as regards salinity and temperature, which fluctuate in both space and time. These characteristics suggest that physical and ecological factors could contribute to the genetic divergence among populations occurring in coastal lagoon and open-coast environments. This study investigates the genetic structure of Holothuria polii at a micro-geographic scale across the Mar Menor coastal lagoon and nearby marine areas, estimating the mitochondrial DNA variation in two gene fragments, cytochrome oxidase I (COI) and 16S rRNA (16S). Dataset of mitochondrial sequences was also used to test the influence of environmental differences between coastal lagoon and marine waters on population genetic structure. All sampled locations exhibited high levels of haplotype diversity and low values of nucleotide diversity. Both genes showed contrasting signals of genetic differentiation (non-significant differences using COI and slight differences using 16S, which could due to different mutation rates or to differential number of exclusive haplotypes. We detected an excess of recent mutations and exclusive haplotypes, which can be generated as a result of population growth. However, selective processes can be also acting on the gene markers used; highly significant generalized additive models have been obtained considering genetic data from 16S gene and independent variables such as temperature and salinity.Coastal lagoons represent habitats with widely heterogeneous environmental conditions, particularly as regards salinity and temperature, which fluctuate in both space and time. These characteristics suggest that physical and ecological factors could contribute to the genetic divergence among populations occurring in coastal lagoon and open-coast environments. This study investigates the genetic structure of Holothuria polii at a micro-geographic scale across the Mar Menor coastal lagoon and nearby marine areas, estimating the mitochondrial DNA variation in two gene fragments, cytochrome oxidase I (COI) and 16S rRNA (16S). Dataset of mitochondrial sequences was also used to test the influence of environmental differences between coastal lagoon and marine waters on population genetic structure. All sampled locations exhibited high levels of haplotype diversity and low values of nucleotide diversity. Both genes showed contrasting signals of genetic differentiation (non-significant differences using COI and slight differences using 16S, which could due to different mutation rates or to differential number of exclusive haplotypes. We detected an excess of recent mutations and exclusive haplotypes, which can be generated as a result of population growth. However, selective processes can be also acting on the gene markers used; highly significant generalized additive models have been obtained considering genetic data from 16S gene and independent variables such as temperature and salinity
A new insight into the influence of habitat on the biochemical properties of three commercial sea cucumber species
This work makes a comparative evaluation of the biochemical profile of three sea commercial cucumber species (Holothuria mammata, H. polii and H. tubulosa) caught from different locations of the Mediterranean Sea (SE Spain). All species had high levels of moisture (from 73.6% in H. mammata to 81.2% in H. tubulosa), crude ash (from 9.61% in H. mammata to 14.7% in H. tubulosa) and protein (3.01% in H. tubulosa to 11.1% in H. mammata). They also had a low fat content, from 0.21% in H. tubulosa to 0.55% in H. mammata. Holothuria polii had intermediate values between the other two species, for all considered variables. All species had adequate protein/lipid ratios (H. mammata, 20:1; H. polii, 23:1; H. tubulosa, 14:1) and low lipid levels, enriched in omega-3 polyunsaturated fatty acids, especially arachidonic acid. The fatty acid profile suggests that H. polii is feeding on sediments more influenced by terrestrial inputs than the remaining species. Holothuria mammata and H. tubulosa are feeding on marine food sources mainly, but also with some terrestrial influence. The most abundant amino acids detected were alanine, arginine, glutamic acid, and glycine. All species had similar contents of essential amino acids (EAA) and ratios of EAA/non-essential amino acids. Holothuria tubulosa had a high content of toxic metals including Cr, Pb and Ni. This work highlights differences in compositional characteristics between different species of the same genus (Holothuria) from different locations.info:eu-repo/semantics/publishedVersio
Effects of fishery protection on biometry and genetic structure of two target sea cucumber species from the Mediterranean Sea
Sea cucumber fisheries are now occurring
in most of the tropical areas of the world, having
expanded from its origin in the central Indo-Pacific.
Due to the overexploitation of these resources and the
increasing demand from Asian countries, new target
species from Mediterranean Sea and northeastern
Atlantic Ocean are being caught. The fishery effects
on biometry and genetic structure of two target species
(Holothuria polii and H. tubulosa) from Turkey, were
assessed. The heaviest and largest individuals of H.
polii were found into the non-fishery area of Kusadasi,
also showing the highest genetic diversity. Similar
pattern was detected in H. tubulosa, but only the
weight was significantly higher in the protected area.
However, the observed differences on the fishery
effects between species, could be explained considering
the different percentage of catches (80% for H.
polii and 20% for H. tubulosa)
Genetic and oceanographic tools reveal high population connectivity and diversity in the endangered pen shell Pinna nobilis
For marine meta-populations with source-sink dynamics knowledge about genetic connectivity
is important to conserve biodiversity and design marine protected areas (MPAs). We evaluate
connectivity of a Mediterranean sessile species, Pinna nobilis. To address a large geographical scale,
partial sequences of cytochrome oxidase I (COI, 590 bp) were used to evaluate phylogeographical
patterns in the Western Mediterranean, and in the whole basin using overlapping sequences from
the literature (243 bp). Additionally, we combined (1) larval trajectories based on oceanographic
currents and early life-history traits and (2) 10 highly polymorphic microsatellite loci collected in the
Western Mediterranean. COI results provided evidence for high diversity and low inter-population
differentiation. Microsatellite genotypes showed increasing genetic differentiation with oceanographic
transport time (isolation by oceanographic distance (IBD) set by marine currents). Genetic
differentiation was detected between Banyuls and Murcia and between Murcia and Mallorca. However,
no genetic break was detected between the Balearic populations and the mainland. Migration rates
together with numerical Lagrangian simulations showed that (i) the Ebro Delta is a larval source for
the Balearic populations (ii) Alicante is a sink population, accumulating allelic diversity from nearby
populations. The inferred connectivity can be applied in the development of MPA networks in the
Western MediterraneanProject MEDEICG funded by the Spanish Ministry of Economy and Competitiveness (CTM2009-07013)IEH was supported by Ramon y Cajal Fellowship RYC2014-14970Spanish Ministry of Economy, Industry and Competitiveness IFCT Investigator Programme-Career Development (IF/00998/2014)MGW and AHE was supported by FCT fellowships SFRH/BPD/63703/2009 and SFRH/BPD/107878/2015National Science Foundation (OCE-1419450)CCMAR team via excellence research line EXCL/AAG-GLO/0661/2012Ciencias del Ma
Environmental variables, habitat discontinuity and life history shaping the genetic structure of Pomatoschistus marmoratus
Coastal lagoons are semi-isolated ecosystems
exposed to wide fluctuations of environmental conditions
and showing habitat fragmentation. These features may
play an important role in separating species into different
populations, even at small spatial scales. In this study, we
evaluate the concordance between mitochondrial (previous
published data) and nuclear data analyzing the genetic
variability of Pomatoschistus marmoratus in five localities,
inside and outside the Mar Menor coastal lagoon (SE
Spain) using eight microsatellites. High genetic diversity
and similar levels of allele richness were observed across
all loci and localities, although significant genic and
genotypic differentiation was found between populations
inside and outside the lagoon. In contrast to the FST values
obtained from previous mitochondrial DNA analyses
(control region), the microsatellite data exhibited significant
differentiation among samples inside the Mar Menor
and between lagoonal and marine samples. This pattern
was corroborated using Cavalli-Sforza genetic distances.
The habitat fragmentation inside the coastal lagoon and
among lagoon and marine localities could be acting as a
barrier to gene flow and contributing to the observed
genetic structure. Our results from generalized additive
models point a significant link between extreme lagoonal
environmental conditions (mainly maximum salinity) and
P. marmoratus genetic composition. Thereby, these environmental
features could be also acting on genetic structure
of coastal lagoon populations of P. marmoratus favoring
their genetic divergence. The mating strategy of P. marmoratus
could be also influencing our results obtained from
mitochondrial and nuclear DNA. Therefore, a special
consideration must be done in the selection of the DNA
markers depending on the reproductive strategy of the
species
Escalas de variabilidad en la estructura genética de las poblaciones de "Diplodus sargus" del Mediterráneo occidental, efectos de la protección de áreas marinas / Mercedes González Wangüemert ; dirección Angel pérez Ruzafa y José Antonio García Charton.
Tesis-Universidad de Murcia.Consulte la tesis en: BCA. GENERAL. ARCHIVO UNIVERSITARIO. T.M. 2716
A new record of Holothuria arguinensis colonizing the Mediterranean Sea
Holothuria arguinensis is reported for the first time on the south-eastern Spanish coast. One specimen of this species was
identified in El Mojo´n (Alicante, Spain, 37850′54.17′′N 0845′39.90′′W). This finding widens the geographical range of
H. arguinensis and demonstrates that its environmental requirements are changing. Future genetic studies in this species
would allow us to improve our understanding of its colonization from the Atlantic Ocean to the Mediterranean Sea.info:eu-repo/semantics/publishedVersio