陸寄居蟹偵測空氣中氣味的能力，是從海洋登陸的關鍵適應之一，其觸角上的受器能夠藉由感知環境線索，協助找尋食物或空殼等重要資源。然而，過往以陸寄居蟹為對象進行的嗅覺生理研究有限，集中在少數明星物種上。本研究建立皺紋陸寄居蟹 (Coenobita rugosus) 的嗅覺電位圖標準操作流程，從結果中分析電位偏移振幅及電位偏移速率兩項指標。為控制個體間基礎生理電位差異，使用線性混合模型 (Linear Mixed Model, LMM)，將嗅覺刺激的種類設定為固定效應、個體設定為隨機效應，進行統計分析。結果顯示個體隨機效應之標準差為21.3 mV，個體間的生理基準值差異龐大。而有多種嗅覺刺激引發皺紋陸寄居蟹的觸角電位負向偏移，其中代表果實發酵味道的酸類敏感度大於代表蛋白質腐敗味道的胺類。引起最大電位偏移的嗅覺刺激為體積濃度1% 的丙酸，其估計值為20.11 mV，且電位偏移速度亦較空氣為快，但在濃度提升至10% 後振幅及速率反而下降，顯示嗅覺受器在高濃度下已達飽和。整體來說，本研究建立嗅覺電位圖實驗流程，並證實皺紋陸寄居蟹能感知酸類及胺類的嗅覺刺激，未來可藉由更廣泛的物質測試來釐清其喜好及行為，將有助於未來擬定相關生態保育措施。

Land hermit crabs can detect airborne odorants, which represented a critical adaptation during their evolutionary transition from marine to terrestrial environments. The receptors on the first antennae can sense environmental cues for empty shells. However, research focused on the olfaction of land hermit crabs is limited, with existing studies heavily concentrated on a few well-known species. In this study, we established the standard operating procedure (SOP) for electroantennogram (EAG) on the wrinkled land hermit crab (Coenobita rugosus), analyzed the EAG amplitude and rate. A linear mixed model (LMM) was used to control for individual variations, with odorant type as the fixed effect and individuals as the random effect. Results showed a standard deviation of 21.3 mV, highlighting the substantial baseline differences. Various odorants triggered negative EAG responses, Acids associated with fruit fermentation showed higher sensitivity than amines associated with putrefaction. Among all tests, 1% propionic acid elicited the strongest EAG response, with an estimated amplitude increase of 20.11 mV and a faster rate than the air control. However, both amplitude and rate decreased when the concentration was increased to 10%, suggesting receptor saturation at higher concentrations. Overall, this study established a standard EAG protocol for the wrinkled land hermit crab and proved its ability to sense both acid and amine odorants. A wider range of chemical compounds can be tested to better understand the preferences and behavior of land hermit crabs, which will facilitate the formulation of ecological conservation strategies.

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