Species of the calcified, articulate coralline Amphiroa are key components of many shallow marine ecosystems. Understanding their mineral composition is important as their susceptibility to dissolution, due to ocean acidification, may vary with mineral composition. We studied the distribution of Mg‐calcite, very high magnesium calcite (VHMC), and dolomite within Amphiroa species to elucidate their mineral properties and susceptibility to dissolution. Results revealed that the asymmetrical X‐ray diffraction (XRD) pattern typical of Amphiroa globally represents high levels of VHMC and dolomite composition carbonate. The dolomite seems most likely to be disordered, but higher resolution XRD is required for confirmation. The calcified long sides of medullary cells have predominantly VHMC/dolomite and the corners have bands of VHMC/dolomite. Epithallial cell walls are low Mg‐calcite, and cortical cells are low Mg‐calcite with bands of VHMC. VHMC/dolomite is more stable than Mg‐calcite, and this may provide a competitive advantage for Amphiroa species as seawater pH declines. Further work is required to determine the metabolic controls on VHMC/dolomite mineral formation.

中文翻译：

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两栖动物中的高镁方解石和白云石组成的碳酸盐（石竹科，科拉利纳莱斯，红藻）：科拉利纳莱中镁含量升高的进一步记载，对气候变化有影响

钙化的，衔接清晰的珊瑚线安非他命的种类是许多浅海生态系统的关键组成部分。了解它们的矿物组成很重要，因为由于海洋酸化，它们对溶解的敏感性可能会随矿物组成而变化。我们研究了Amphiroa物种中的Mg-方解石，非常高的方解石（VHMC）和白云石的分布，以阐明它们的矿物特性和易溶性。结果表明，Amphiroa具有典型的不对称X射线衍射（XRD）模式全球范围内代表着高含量的VHMC和白云石组成的碳酸盐。白云石似乎最有可能是无序的，但是需要更高的分辨率XRD才能确认。髓质细胞的钙化长边主要是VHMC /白云石，而角上有VHMC /白云石带。上皮细胞壁是低镁方解石，皮质细胞是低镁方解石，带VHMC。VHMC /白云石比方解石Mg稳定，随着海水pH值的降低，这可能为Amphiroa物种提供竞争优势。需要进一步的工作以确定对VHMC /白云石矿物质形成的代谢控制。