Six new bromoindole derivatives, aplicyanins A–F (1–6), have been isolated from the CH2Cl2/MeOH extract of the tunicate Aplidium cyaneum collected in Antarctica. Their structures were determined by extensive analysis of their spectroscopic features, particularly 1D and 2D NMR spectra, and comparison with related compounds. Cytotoxic and antimitotic activities were found for compounds 2 and 4–6.