Fig. 3

Schematic representation of the change in size during the seasonal life cycle in both sexes of Lineus viridis. It should be noted that while older females are observable throughout the year, males can only be identified during gonad maturation and reproductive phase. First-year females can be discriminated by not having formed gonopores yet. When the gonopores in females appear for the first time they become indistinctive from older females (hence the decrease in mean body length in older females between October and November). Infertile animals not shown