Fig. 1

The female reproductive cycle of Nephrops norvegicus. a In the regular cycle, ovaries develop through darkening shades of green (stages 1a to 4). Females in late ovary maturation (stage 4) spawn in summer and resorb few remaining oocytes in the spent ovary afterwards (partial resorption, stage 5a). However, a proportion of females proceed along a different pathway once maturation is almost complete (stage 4). Instead of spawning, these females completely resorb the green yolk in their ovaries indicated by increasing shades of yellow (stages 5b and 1b). These females skip one reproductive cycle and reenter the regular cycle presumably at stage 2. b The process of full resorption (5b to 1b) is characterised by a mottled appearance with a mix of green and yellow in the ovary. With the progressive resorption of the green yolk, the proportion of yellow increases until all the green yolk has disappeared in stage 1b. The license number is 4926480336055