First detailed description of the burying behaviour of a bottletail squid, Sepiadarium kochii Steenstrup, 1881

摘要

Bottletail squids (Cephalopoda: Sepiadariidae) spend the daytime buried in sediment; however, their burying behaviour has not yet been described in detail. In the present study, the burying pattern of a single tropical bottletail squid Sepiadarium kochii Steenstrup, 1881 is analysed for different behavioural characteristics. Burying in S. kochii consists of a rapid sequence of strong, alternating forward- and backward directed funnel jets which obscure the individual almost fully with sediment, followed by a single flinging movement of the dorsolateral arm pair to cover the remaining exposed body parts with sand. A comparison of the burying pattern of S. kochii with that of closely related bobtail squids (Cephalopoda: Sepiolidae) is drawn. Moreover, differences between these two cephalopod families in terms of the execution and duration of their burying procedure as well as its behavioural use are discussed.