Meeting Abstract

80.2  Tuesday, Jan. 6  Angkor Wat on the intertidal mudflats: Towers built by the manicure crab Cleistostoma dilatatum (de Haan) for thermo-regulated ventilation KIM, Tae Won*; KIM, Sunhye; CHOI, Jae Boong; CHOE, Jae Chun; Ewha Woman’s University; Sungkyunkwan University; Sungkyunkwan University; Ewha Woman’s University ktwon@ewha.ac.kr

In Kanghwa Island, South Korea, the manicure crab Cleistostoma dilatatum living on the mudflat constructs an extraordinary tower at the entrance of its own burrow. The tower is the highest ever known among structures built by various crabs living on the intertidal flats. The tower has a hole connected to the burrow of the crab, which has a very small diameter (1-3mm) on its top but becomes wider downwards. The function of the structure is unknown but the possible role of ventilation has been suggested. The crabs build towers at the beginning of neap tides when the water does not cover the habitat and the sediment becomes dry. The mud surface temperature decreases as it comes to the center of the tower and this probably would help air on the top mixing with air below the burrow. The result suggests that the tower of C. dilatatum has been evolved for optimal ventilation. The tower of C. dilatatum is thought as an adaptive phenotype for enduring dryness on the mudflat during neap tides without being active on the mudflat.