@article {5619, title = {Effect of CO2{\textendash}induced ocean acidification on the early development and shell mineralization of the European abalone (Haliotis tuberculata)}, journal = {Journal of Experimental Marine Biology and Ecology}, volume = {508}, year = {2018}, pages = {52 - 63}, abstract = {

Ocean acidification is a major global stressor that leads to substantial changes in seawater carbonate chemistry, with potentially significant consequences for calcifying organisms. Marine shelled mollusks are ecologically and economically important species providing essential ecosystem services and food sources for other species. Because they use calcium carbonate (CaCO3) to produce their shells, mollusks are among the most vulnerable invertebrates to ocean acidification, with early developmental stages being particularly sensitive to pH changes. This study investigated the effects of CO2-induced ocean acidification on larval development of the European abalone Haliotis tuberculata, a commercially important gastropod species. Abalone larvae were exposed to a range of reduced pHs (8.0, 7.7 and 7.6) over the course of their development cycle, from early-hatched trochophore to pre-metamorphic veliger. Biological responses were evaluated by measuring the survival rate, morphology and development, growth rate and shell calcification. Larval survival was significantly lower in acidified conditions than in control conditions. Similarly, larval size was consistently smaller under low pH conditions. Larval development was also affected, with evidence of a developmental delay and an increase in the proportion of malformed or unshelled larvae. In shelled larvae, the intensity of birefringence decreased under low pH conditions, suggesting a reduction in shell mineralization. Since these biological effects were observed for pH values expected by 2100, ocean acidification may have potentially negative consequences for larval recruitment and persistence of abalone populations in the near future.

}, keywords = {Abalone, larval development, Ocean acidification, Shell mineralization}, issn = {0022-0981}, doi = {https://doi.org/10.1016/j.jembe.2018.08.005}, url = {http://www.sciencedirect.com/science/article/pii/S0022098117304070}, author = {Nathalie Wessel and Sophie Martin and Badou, Aicha and Philippe Dubois and Sylvain Huchette and Vivien Julia and Flavia Nunes and Ewan Harney and Christine Paillard and St{\'e}phanie Auzoux-Bordenave} } @article {4687, title = {Phylogeography of the reef-building polychaetes of the genus Phragmatopoma in the western Atlantic Region}, journal = {Journal of Biogeography}, volume = {44}, year = {2017}, month = {06/2017}, pages = {1612-1625}, abstract = {

Aim

To verify the synonymy of the reef-building polychaete Phragmatopoma caudata (described for the Caribbean) and Phragmatopoma lapidosa (described for Brazil) using molecular data. To evaluate the patterns of genetic diversity and connectivity among populations from Florida to South Brazil.

Location

Intertidal zone in the western Atlantic biogeographical Region: Brazil, eastern Caribbean and Florida (USA).

Methods

DNA sequence data from one mitochondrial (cox-1) and one nuclear ribosomal (ITS-1) loci were obtained from 11 populations of P. caudata spanning the coasts of Brazil, eastern Caribbean and Florida. Phylogenetic relationships among populations of P. caudata and other members of the genus were inferred by Bayesian methods. Population differentiation was evaluated by Bayesian analysis of population structure (baps), AMOVA and pairwise φst. Demographic history was inferred by Bayesian skyline plots.

Results

Phylogenetic inference supported the interpretation of a single species of Phragmatopoma spanning the Brazilian and Caribbean Provinces of the western Atlantic Region. Little population structure was observed across the species distribution, with the exception of the Florida population. The baps analysis supported a 2-population model, with population differentiation being strong and significant between Florida and all other Atlantic populations for cox-1, and significant between Florida and most populations for ITS-1. Differences in genetic diversity were not significant between Caribbean and Brazilian populations, although several populations in Brazil had low values for diversity indices. Bayesian skyline plots indicate population expansion starting at c.\ 200\ ka.

Main conclusions

Phragmatopoma caudata is able to maintain genetic connectivity across most of its geographical range, with population differentiation being observed only between Florida and all other localities, possibly due to ecological speciation in the transition zone between tropical and subtropical environments. Long-distance connectivity across much of the species range is likely the result of long-lived larvae that are tolerant to a wide range of environmental conditions.

}, doi = {10.1111/jbi.12938}, author = {Flavia Nunes and Alain Van Wormhoudt and Larisse Faroni Perez and J{\'e}r{\^o}me Fournier} }