Neuroecology Group, School of Animal Biology and The UWA Oceans Institute, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, WA 6009, Australia; Coastal Systems Laboratory, School of Geography, Planning and Environmental Management, The University of Queensland, Sir Fred Schonell Drive, Brisbane, QLD 4072, Australia.
Zoology (Jena). 2013 Oct;116(5):270-6. doi: 10.1016/j.zool.2013.05.002. Epub 2013 Jul 19.
The electrosensory system is found in all chondrichthyan fishes and is used for several biological functions, most notably prey detection. Variation in the physical parameters of a habitat type, i.e. water conductivity, may influence the morphology of the electrosensory system. Thus, the electrosensory systems of freshwater rays are considerably different from those of fully marine species; however, little research has so far examined the morphology and distribution of these systems in euryhaline elasmobranchs. The present study investigates and compares the morphology and distribution of electrosensory organs in two sympatric stingray species: the (euryhaline) estuary stingray, Dasyatis fluviorum, and the (marine) blue-spotted maskray, Neotrygon kuhlii. Both species possess a significantly higher number of ventral electrosensory pores than previously assessed elasmobranchs. This correlates with a diet consisting of benthic infaunal and epifaunal prey, where the electrosensory pore distribution patterns are likely to be a function of both ecology and phylogeny. The gross morphology of the electrosensory system in D. fluviorum is more similar to that of other marine elasmobranch species, rather than that of freshwater species. Both D. fluviorum and N. kuhlii possess 'macro-ampullae' with branching canals leading to several alveoli. The size of the pores and the length of the canals in D. fluviorum are smaller than in N. kuhlii, which is likely to be an adaptation to habitats with lower conductivity. This study indicates that the morphology of the electrosensory system in a euryhaline elasmobranch species seems very similar to that of their fully marine counterparts. However, some morphological differences are present between these two sympatric species, which are thought to be linked to their habitat type.
电感受器系统存在于所有软骨鱼类中，用于多种生物学功能，最显著的是猎物检测。栖息地类型的物理参数的变化，即水的电导率，可能会影响电感受器系统的形态。因此，淡水鳐的电感受器系统与完全海洋物种的电感受器系统有很大的不同；然而，迄今为止，很少有研究检查过这些系统在广盐性软骨鱼类中的形态和分布。本研究调查和比较了两种同域鳐鱼的电感受器器官的形态和分布：（广盐性）河口鳐，Dasyatis fluviorum，和（海洋）蓝斑蒙面鳐，Neotrygon kuhlii。这两个物种都拥有比以前评估的软骨鱼类多得多的腹侧电感受器孔。这与以底栖无脊椎动物和底栖无脊椎动物为食的饮食相关，其中电感受器孔分布模式可能是生态和系统发育的函数。D. fluviorum 的电感受器系统的大体形态更类似于其他海洋软骨鱼类，而不是淡水物种。D. fluviorum 和 N. kuhlii 都具有带有分支管通向几个肺泡的“大壶腹”。D. fluviorum 中的孔的大小和管的长度都比 N. kuhlii 小，这可能是对电导率较低的栖息地的适应。本研究表明，广盐性软骨鱼类的电感受器系统的形态似乎与完全海洋物种的电感受器系统非常相似。然而，这两种同域物种之间存在一些形态差异，这些差异被认为与它们的栖息地类型有关。
