AbstractA virtual image showing ascidian Ciona intestinalis larvae swimming to "corals" located at the bottom of the picture. On top right is a tailbud embryo still in the chorion before hatching. Swimming larvae are carrying constructs driving the expression of green fluorescent proteins in epidermis. Larvae become juveniles through metamorphosis (lower right). Juveniles and adult neural complex pictures derive from a transgenic line with Ror‐b regulatory sequences, which drives yellow fluorescent protein expression at the top of endostyles in juveniles and at the margins of the so‐called ciliated funnels in neural complexes. The corals were reconstructed from details of two adult neural gland complexes artificially merged. Our ascidian facilities in closed‐systems contribute to the maintenance of such transgenic lines. See Joly et al., Developmental Dynamics 236:1832–1840.