Schematic outline of the reproductive systems of the taxa of the families Paracoryphellidae and Flabellinopsidae integrated with molecular phylogenetic data. Colour indication of reproductive system characters: ampulla – green; body wall – gray; distal receptaculum seminis – red; female gland mass – yellow; female genital opening – orange; penis and male genital opening – dark blue; penial external collar – lilac; penial sheath – pale blue; prostate and prostatic vas deferens – turquoise.