Cidaroids spines facing ocean acidification

• Published in: Marine Environmental Research
• Main Authors: Dery, A., Tran, P. D., Compère, Philippe, Dubois, Philippe
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elsevier Ltd 2018
• Subjects: Benthos; Epibionts; Magnesium concentration; Minerals; Ocean acidification; Sea urchin; Spine; Acidification; Biofilms; Calcium carbonate; Dissolution; Facings; Magnesium; Mammals; Shellfish; Magnesium concentrations; Ocean acidifications; Seawater corrosion; Article; Cidaroida; Echinoidea; Euechinoidea; Adaptation; Physiological; Animals; Hydrogen-Ion Concentration; Oceans and Seas; Sea Urchins; Seawater; Temperature; Water Pollutants; Life sciences; Aquatic sciences & oceanology; Sciences du vivant; Sciences aquatiques & océanologie
• Online Access: https://orbi.uliege.be/handle/2268/236833; https://doi.org/10.1016/j.marenvres.2018.03.012

peer reviewed When facing seawater undersaturated towards calcium carbonates, spines of classical sea urchins (euechinoids) show traces of corrosion although they are covered by an epidermis. Cidaroids (a sister clade of euechinoids) are provided with mature spines devoid of epidermis, which makes them, at first sight, more sensitive to dissolution when facing undersaturated seawater. A recent study showed that spines of a tropical cidaroid are resistant to dissolution due to the high density and the low magnesium concentration of the peculiar external spine layer, the cortex. The biofilm and epibionts covering the spines was also suggested to take part in the spine protection. Here, we investigate the protective role of these factors in different cidaroid species from a broad range of latitude, temperature and depth. The high density of the cortical layer and the cover of biofilm and epibionts were confirmed as key protection against dissolution. The low magnesium concentration of cidaroid spines compared to that of euechinoid ones makes them less soluble in general. © 2018 Elsevier Ltd