Departamento de Biologia, Faculdade de Filosofia Ciência e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil.
J Comp Physiol B. 2012 Dec;182(8):997-1014. doi: 10.1007/s00360-012-0665-8. Epub 2012 Apr 26.
Decapod crustaceans exhibit a wide range of osmoregulatory patterns and capabilities from marine osmoconformers to brackish and freshwater hyperregulators to terrestrial hyporegulators. The principal gill salt transport mechanisms proposed to underlie the ability of the better-known taxa to occupy these specific habitats are examined here. Traditional thinking suggests that a graduated series of successively stronger adaptive mechanisms may have driven the occupation of ever more dilute osmotic niches, culminating in the conquest of freshwater and dry land. However, when habitat and osmoregulatory parameters are analyzed quantitatively against the phylogenies of the taxa examined, as illustrated here using a palaemonid shrimp clade, their association becomes questionable and may hold true only in specific cases. We also propose a putative evolution for gill epithelial ion pump and transporter arrangement in a eubrachyuran crab clade whose lineages occupy distinct osmotic niches. By including the systematics of these selected groups, this review incorporates the notion of a protracted time scale, here termed 'phylophysiology', into decapod osmoregulation, allowing the examination of putative physiological transformations and their underlying evolutionary processes. This approach assumes that species are temporally linked, a factor that can impart phylogenetic structuring, which must be considered in comparative studies. Future experimental models in decapod osmoregulatory physiology should contemplate the phylogenetic relationships among the taxa chosen to better allow comprehension of the transformations arising during their evolution.
十足目甲壳动物表现出广泛的渗透调节模式和能力，从海洋等渗生物到半咸水和淡水高渗调节者到陆生低渗调节者。这里检查了为更好地了解这些特定栖息地的已知分类群的能力而提出的主要鳃盐转运机制。传统观点认为，一系列逐渐增强的适应性机制可能推动了对更稀释渗透小生境的占领，最终导致对淡水和旱地的征服。然而，当根据所检查的分类群的系统发育对栖息地和渗透调节参数进行定量分析时，如图所示，使用 Palaemonid 虾类群，它们的关联变得值得怀疑，并且可能仅在特定情况下成立。我们还提出了一个假定的鳃上皮离子泵和转运体排列的进化，在一个真短尾蟹类群的进化枝中，它们的谱系占据不同的渗透小生境。通过包括这些选定群体的系统发育，本综述将“时间生理学”的概念纳入十足目渗透调节中，允许检查假定的生理转化及其潜在的进化过程。这种方法假设物种在时间上是相关的，这是一个可以赋予系统发育结构的因素，在比较研究中必须考虑到这一点。十足目渗透调节生理学的未来实验模型应该考虑到所选择的分类群之间的系统发育关系，以便更好地理解它们在进化过程中产生的转化。
