Summary of the impact of low <i>p</i>CO₂ (27063 µatm) on <i>S. roscoffensis</i> life cycle.

<p>Summary of the impact of low <i>p</i>CO₂ (27063 µatm) on <i>S. roscoffensis</i> life cycle.</p

Impact of a range of <i>p</i>CO₂ on the growth rate of newly hatched juveniles in presence of their photosymbiotic algae (9 days exposure; Experiment 3).

<p>A significant logarithmic relationships was observed between <i>p</i>CO₂ and juvenile growth rate (F = 7.84, p<0.019), the growth rate being 19% faster in the highest test <i>p</i>CO₂ (27 k µatm) compared to the lowest (0.4 k µatm).</p

Impact of a range of <i>p</i>CO₂ on: A. number of eggs produced per female; B. number of eggs per cocoon; C. number of cocoon produced per female (experiment 4).

<p>The number of eggs produced per female was 3 times higher in high compared to low <i>p</i>CO₂ (27 k vs 0.4 k µatm) and a significant logarithmic relationship was observed between the two parameters (F = 8.36, p<0.016; <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029568#pone-0029568-g003" target="_blank">Figure 3A</a>). This was the consequence of an increased number of cocoon produced per female (significant logarithmic relationship, F = 7.79, p<0.02; <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029568#pone-0029568-g003" target="_blank">Figure 3B</a>) with no effect on the number of eggs per cocoon (non significant logarithmic relationship, F = 0.43, p<0.53; <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029568#pone-0029568-g003" target="_blank">Figure 3C</a>).</p

<i>Symsagittifera roscoffensis</i> after a 24 h exposure to seawater with different pH (experiment 5).

<p>Animals in the lower pH started to bleach.</p

Luminescence capabilities of <i>Amphiura filiformis</i> adults (n = 30).

Measurements of the coelenterazine content (ng. g-1), the luciferase activity (109 q. g-1. s-1), and the light emission after KCl depolarization and cholinergic stimulation (q. g-1) in the arm tissue. (DOCX)</p

Luminescence capabilities of <i>Amphiura filiformis</i> larval stages from male and female gonads to 32 days post-fertilization (dpf).

(A) Coelenterazine content (ng g-1) is significantly higher in the female gonads, (B) Luciferase activity (109 q g-1 s-1) raised at 32 dpf, (C) Total light emission (109 q g-1) with KCl stimulation (109 q g-1) increased significantly 32 days after fertilization. Values are expressed as mean ± s.e.m. Asterisks indicate statistical differences between each larval stage with n≧6 (i) Kruskal–Wallis ANOVA and Wilcoxon multiple comparisons for coelenterazine content and total light emission, (ii) ANOVA and Tukey’s test for the luciferase activity; *P<0.05.</p

Immunolocalization of the Renilla-like luciferase (in red) in arm tissue from an <i>Amphiura filiformis</i> adult <i>po</i>, <i>podia</i>, <i>sp</i>, <i>spine</i>.

Immunolocalization of the Renilla-like luciferase (in red) in arm tissue from an Amphiura filiformis adult po, podia, sp, spine.</p

Spearman correlation between developmental stage and luminometric measurement.

Spearman correlation between developmental stage and luminometric measurement.</p

Typical curve obtained for the 32 dpf juvenile of <i>Amphiura filiformis</i> in luminometric analyses.

(A) Coenleterazine typical curve. (B) Acetylcholine (ACh 1mM) characteristic curve. (DOCX)</p

Immunolocalization of the <i>Renilla</i>-like luciferase (in red) in <i>Amphiura filiformis</i> larval stages; (A) 15 days, (B) 25 days, (C) 32 days post-fertilization, and (D) juveniles.

aa, arm article; di, disk; dt, digestive tract; es, oesophagus; jr, juvenile rudiment; jw, jaws; mo, mouth opening; po, podia; pd, pentameric development; sk, skeleton rod; sp, spine; td, tip of the developing arm. Scale bar: 40 μm.</p