Mating behavior of nemerteans: present knowledge and future directions

摘要: In most nemertean species, members of the two sexes aggregate before fertilization takes place. Few specific studies on mating behaviour nemerteans have been conducted but several observational reports indicate that important processes known from other organisms, such as sexual selection and sperm competition, may also be at work in nemerteans. Herein, we review some these observations discuss their possible implications. We produce a summary table reproduce observations, placing them an evolutionary context. Four types gamete‐transfer mechanisms are distinguished: (1) free‐spawning, where both release gametes freely into water column; (2) mucus‐spawning, released within mucus matrix; (3) internal fertilization, spermatozoans transferred to immediate vicinity oviducts, which they penetrate; (4) gamete transfer aided by structures. While little is about last mechanism, anecdotal ...