The annual reproductive cycle ofAchaetohonellia maculata Fisher (Echiura: Bonellidae)
This study is the first to detail the annual reproductive cycle of any echiuran. Here the annual reproductive cycle ofAchaetohonellia maculata Fisher is described. Oocytes first appear in the coelomic fluid in late spring or early-summer. During fall and winter, gametes production and differentiation continue. Differentiation of gametes lasts four to six months. Spawning occurs in spring. Since the niaks are the permanent residents in the gone duct of the female, the fertilization is internal in Boneliidae. Temperature of the sea water probably is the most important exogenous factor controlling the reproductive cycle. Individuals reach sexual maturity when they are one year old.