Many organisms employ toxic compounds for protection against predators. To understand the effectiveness of such compounds, chemoecological studies often use brine shrimp (Artemia spp.) as a model organism instead of more ecologically relevant species. This is mostly because brine shrimp assays are simple and quick, but also due to the ethical implications associated with inducing harm to vertebrate predators in toxicity assays. In this study, we examined whether brine shrimp assays produce similar results to ichthyological toxicity assays with the aim of validating the use of brine shrimp as a preliminary screening tool. We extracted compounds from eight nudibranch molluscs including six species that we consider to signal their chemical defenses via warning coloration to visually hunting vertebrate predators. We tested the relative toxicity of these compounds against brine shrimp and a vertebrate potential predator, the blue-green damselfish (Chromis viridis). We found that extracts toxic to brine shrimp were also toxic to damselfish; however, extracts non-toxic to brine shrimp may still be toxic to damselfish. We also produced and tested mantle vs whole-body extracts for some nudibranch species, which exhibited similar toxicities in both assays except for the whole-body extract of Goniobranchus splendidus which was harmless to shrimp but toxic to fish, while the mantle extract was toxic to both. Overall, we argue that the brine shrimp assay can reasonably indicate the potential toxicity of a compound to fish, but additional experiments with more ecologically relevant predators are required if a no dose-response is observed against brine shrimp.

许多生物使用有毒化合物来抵御捕食者。为了了解这些化合物的有效性，化学生态学研究经常使用丰年虾（卤虫）spp.) 作为模式生物而不是生态相关的物种。这主要是因为盐水虾测定简单快捷，但也由于与在毒性测定中对脊椎动物捕食者造成伤害相关的伦理影响。在这项研究中，我们检查了丰年虾检测是否产生与鱼类毒性检测相似的结果，目的是验证丰年虾作为初步筛选工具的使用。我们从八种裸鳃类软体动物中提取了化合物，其中包括六种我们认为通过警告着色向视觉捕猎脊椎动物捕食者发出化学防御信号的物种。我们测试了这些化合物对盐水虾和脊椎动物潜在捕食者蓝绿色雀鲷（Chromis viridis ）的相对毒性）。我们发现对盐水虾有毒的提取物对雀鲷也有毒；然而，对盐水虾无毒的提取物可能对雀鲷仍然有毒。我们还生产并测试了一些裸鳃类动物的地幔与全身提取物，除了对虾无害但对鱼类有毒的Goniobranchus splendidus全身提取物，而地幔提取物对两个都。总的来说，我们认为丰年虾试验可以合理地表明一种化合物对鱼类的潜在毒性，但如果没有观察到对丰年虾的剂量反应，则需要对更具生态相关性的捕食者进行额外的实验。