Morphology of the suckers for hunting behavior in broadclub cuttlefish (Sepia latimanus)

Abstract

AbstractCuttlefish has eight arms and two tentacles that it uses to catch prey. Cuttlefish finds prey, extends its tentacles, catches the prey using tentacular clubs, and retracts the prey. After retraction, the cuttlefish holds and transfers the prey to its mouth using its arms. Since this efficient unique predation is one of the significant factors that have made the cuttlefish a keystone species in marine food ecosystems, many behavioral studies have been conducted. However, the morphological benefit of the sucker on the arms and tentacles for capturing behavior is poorly understood. Here, we observed the relationship between the morphology and function of the arm and tentacular suckers of the broadclub cuttlefish qualitatively and quantitatively. The arm sucker protrudes from the arm surface and has a shorter sucker pedicel length than that of the tentacular sucker. The longest point of the inner sucker ring of the arm sucker is on the aboral side. These are adaptive features to hold and transfer prey effectively from the arms to the mouth. In contrast, the tentacular sucker is stored in the groove of the tentacular club and has a longer sucker stalk length than that of the arm sucker. The longest point of the inner sucker ring of the tentacular sucker is on the outer direction of the holdfast of the tentacular stalk. These are adaptive features for the rapid retraction of moving prey. The results indicate that cuttlefish's arm and tentacular sucker structures reflect their practical use for prey capture.