Abstract Gmelinoides fasciatus is a successful invasive amphipod (Amphipoda, Crustacea) that dispersed from Lake Baikal to various waterbodies. Here we studied whether Baikal conditions are optimal for G. fasciatus in terms of thermotolerance and investigated lethal temperatures, 70 kDa heat shock protein level, energy metabolism, and antioxidant defense of animals from three geographically distant waterbodies under changing temperatures. We used acute heat exposure to 28 °C to assess the median lethal times and gradual temperature increase from 6 °C to determine the lethal temperatures. Mortality under heat shock was explainable by the baseline content of Hsp70 that correlated with thermal history. But it was not the case under gradual temperature increase where Hsp70 levels became similar and the mortality pattern changed. The most thermotolerant amphipods from the Gulf of Finland demonstrated a higher amount of free glucose during the temperature increase that may be related to the higher salinity of this waterbody and less energy required for ion regulation. Even though concentrations of major physiological ions in Lake Baikal are lower than in Lake Ladoga, G. fasciatus from Ladoga was slightly more sensitive to the gradual temperature increase. This difference could be explained by the influence of high levels of humic and other potentially toxic substances in Lake Ladoga indicated by increased activities of catalase and glutathione S-transferase. Importantly, all G. fasciatus populations accumulated relatively low levels of lactate during the temperature increase, which may reflect the ability of this invasive species to effectively maintain aerobic metabolism under various conditions.

中文翻译：

---

栖息在远处水体的入侵者片脚类 Gmelinoides fasciatus (Stebbing, 1899) 在高温下表现出耐受性和能量代谢的差异

摘要 Gmelinoides fasciatus 是一种成功的侵入性片脚类动物（Amphipoda, Crustacea），从贝加尔湖扩散到各种水体。在这里，我们研究了贝加尔湖条件是否在耐热性方面最适合 G. fasciatus，并研究了温度变化下来自三个地理上遥远的水体的动物的致死温度、70 kDa 热休克蛋白水平、能量代谢和抗氧化防御。我们使用 28 °C 的急性热暴露来评估中位数致死时间和从 6 °C 逐渐升高的温度以确定致死温度。热休克下的死亡率可以通过与热史相关的 Hsp70 的基线含量来解释。但在逐渐升温的情况下情况并非如此，Hsp70 水平变得相似并且死亡率模式发生了变化。芬兰湾最耐热的片脚类动物在温度升高期间表现出较高量的游离葡萄糖，这可能与该水体的盐度较高和离子调节所需的能量较少有关。尽管贝加尔湖中主要生理离子的浓度低于拉多加湖，但拉多加的 G. fasciatus 对逐渐升温的敏感性略高。这种差异可以通过拉多加湖中高浓度腐殖质和其他潜在有毒物质的影响来解释，这表明过氧化氢酶和谷胱甘肽 S-转移酶的活性增加。重要的是，所有 G. fasciatus 种群在温度升高期间积累的乳酸水平相对较低，