Fig. 3

Early development in B. undatum. (a) Early pediveliger stage with empty midgut indicating few or no nurse eggs were consumed. (b) Veligers of varying sizes developing alongside each other; within one capsule and following nurse egg consumption. (c) Early pediveliger stage with individual nurse eggs still clearly discernible under the shell. (d) Well-developed mid pediveliger stage with velar lobes still present. Growth lines can be observed on shell. n nurse egg, vl velar lobe, mg midgut, vm visceral mass, s shell, sg siphonal groove, t tentacle, e eye, f foot, gl growth lines. Scale bars represent 500 μm