Female gonad morphology of centropages furcatus (dana, 1852)

Centropages furcatus is a dominant species of the planktonic community in the Ensenada de La Paz, Baja California Sur, Mexico. Little is known about gonad morphology and maturation of this species, and that knowledge is key for understanding the reproductive activity and the mode of eproduction of C. furcatus. The histological analysis revealed that, similar to most calanoid copepods, the sac-shaped ovary of C. furcatus is located dorsally to the centre of the prosoma; oocyte maturation takes place outside the ovary. Besides, in agreement with the Calanus-type gonad, most oocyte development stages occur simultaneously, and frequently many oocytes mature synchronously. However, the spatial location of oocytes differs from the one described for the Calanus-type gonad. In C. furcatus, previtellogenic oocytes are arranged in an outer layer spreading longitudinally and across the circumference of the prosoma; oocyte growth and maturation takes place radially towards the b dy centre. For this reason, a new gonad morphology type is hereby proposed for C. furcatus, naming it furcatus-type.