Fig. 1

a: Living specimen of Magelona mirabilis. ca: caudal; fr: frontal; mo: mouth; pa: palp. b,c: Volume rendering of Magelona mirabilis and 3D-reconstruction of the central nervous system (yellow). apbr: anterior part of brain. dpbr: dorsal part of brain; lmc: lateral medullary cord; lpbr: lateral part of brain; mo: mouth; pa: palp