Functional significance of the sexual dimorphism in the cephalic appendages of euchaeta rimana bradford

摘要

In Euchaeta rimana the cephalic appendages become profoundly sexually dimorphic at the final molt. The maxillipeds and robust maxillae, which are related to the predatory nature of this pelagic marine copepod are fully functional on the fifth copepodid (CV) males and adult females. The presumed prey detection sensory apparatus, a paired 4-point setal array on the antennules, is located within the capture volume of the feeding current of the CVs and adult females. SEMs reveal specialized basal articulations of the straight and curved setae of this array, that allow setal rotations that streamline the anten- nule during escape movements.