Dero digitata - fission zone, advanced stage

DIC image of an advanced stage fission zone (stage D/E) in a Dero digitata worm. The obliquous fission plane separates the developing new tail (left side) and new head (right side). In the new tail, numerous new segments can be already be distinguished, along with a well developed branchial pavillion. In the new head, brain and pharynx are already fully differentiated.