Ocean acidification is projected to inhibit the biogenic production of calcium carbonate skeletons in marine organisms. Antarctic waters represent a natural environment in which to examine the long‐term effects of carbonate undersaturation on calcification in marine predators. King crabs (Decapoda: Anomura: Lithodidae), which currently inhabit the undersaturated environment of the continental slope off Antarctica, are potential invasives on the Antarctic shelf as oceanic temperatures rise. Here, we describe the chemical, physical, and mechanical properties of the exoskeleton of the deep‐water Antarctic lithodid Paralomis birsteini and compare our measurements with two decapod species from shallow water at lower latitudes, Callinectes sapidus (Brachyura: Portunidae) and Cancer borealis (Brachyura: Cancridae). In Paralomis birsteini, crabs deposit proportionally more calcium carbonate in their predatory chelae than their protective carapaces, compared with the other two crab species. When exoskeleton thickness and microhardness were compared between the chelae and carapace, the magnitude of the difference between these body regions was significantly greater in P. birsteini than in the other species tested. Hence, there appeared to be a greater disparity in P. birsteini in overall investment in calcium carbonate structures among regions of the exoskeleton. The imperatives of prey consumption and predator avoidance may be influencing the deposition of calcium to different parts of the exoskeleton in lithodids living in an environment undersaturated with respect to calcium carbonate.

中文翻译：

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南极帝王蟹Paralomis birsteini的外骨骼特征

预计海洋酸化会抑制海洋生物中碳酸钙骨架的生物生成。南极水域代表了一种自然环境，在其中可以研究碳酸盐不饱和度对海洋捕食者钙化的长期影响。帝王蟹（十足目：Anomura：Lithodidae）目前居住在南极洲大陆斜坡的欠饱和环境中，随着海洋温度的升高，它们可能是南极大陆架上的潜在入侵者。在这里，我们描述了深水南极石质巨蜥Parasteinis birsteini的外骨骼的化学，物理和力学性质，并将我们的测量结果与来自低纬度的浅水Call的两个十足类物种 Callinectes sapidus（Brachyura：Portunidae）和北方巨蟹（Brachyura：Cancridae）。与其他两种蟹相比，在Paralomis birsteini中，蟹在其捕食性螯虾中沉积的碳酸钙比其保护性甲壳成比例的多。当比较chel和甲壳的外骨骼厚度和显微硬度时，P。birsteini的这些身体区域之间差异的幅度明显大于其他测试物种。因此，伯氏疟原虫似乎存在更大的差异。外骨骼区域之间碳酸钙结构的总体投资。消耗猎物和避免捕食动物的必要性可能会影响到生活在相对于碳酸钙而言饱和的环境中的石怪中钙沉积到外骨骼不同部分的情况。