Temperature plays a major role in controlling species' distributions, and small-scale variation in the thermal environment are potentially an important factor that governs distributions on a local scale. For untangling the roles of behavioral and physiological adaptations on species' distribution at a small-scale level, we carried out a comparative study of two mudflat snails (genus Cerithidea) by determining these congeners' burying behavior, lethal temperature, cardiac performance and heat-shock protein (hsp70) gene expression. These two sympatric snails occupy different microhabitats on the upper intertidal mudflat. During periods of emersion, C. cingulata inhabits the open mudflat and C. largillierti usually aggregates around small rocks on the upper intertidal mudflat. Our results indicate that the two Cerithidea congeners show different behavioral and physiological responses to high temperature. Compared to C. largillierti, C. cingulata prefers to bury into the mud, has a higher thermal limit and a higher level of inducible expression of hsp70 mRNA, implying important roles of behavioral and physiological adaptations to the harsh thermal environment on the open mudflat. Furthermore, results of generalized additive modelling (GAM) analysis of cardiac performance and coefficient of variation (CV) of hsp70 mRNA expression showed high inter-individual variation in C. cingulata. These results highlight the importance of behavioral and physiological adaptions in sympatric species' distributions on the mudflat and help to shed light on the mechanisms of how small-scale differences in the thermal environment shape sympatric species’ distributions.

温度在控制物种分布中起着重要作用，热环境的小范围变化可能是控制局部范围分布的重要因素。为了弄清楚行为和生理适应在小规模水平上对物种分布的作用，我们通过确定这两种泥flat的埋葬行为，致死温度，心脏性能和热量，对这两种泥螺进行了比较研究（Cerithidea属）。休克蛋白（hsp70）基因表达。这两个同卵蜗牛在潮间带上滩处于不同的微生境。在出苗期，丁香梭菌（C. cingulata）居住在开阔的滩涂和拉美梭菌（C. largillierti）通常聚集在潮间带上滩上的小岩石周围。我们的结果表明，两个Cerithidea同源物对高温表现出不同的行为和生理响应。与largillierti相比，cingulata C.更喜欢掩埋在泥浆中，具有较高的热极限和较高水平的hsp7 0 mRNA的诱导表达水平，这暗示了行为和生理适应对露天泥滩的恶劣热环境的重要作用。此外，对心脏表现和hsp7 0 mRNA表达的变异系数（CV）进行的通用加性建模（GAM）分析结果显示，扣带回之间存在很高的个体差异。。这些结果突出了行为和生理适应对泥滩上同族物种分布的重要性，并有助于揭示热环境中小尺度差异如何影响同族物种分布的机制。