We use the dispersive Fourier transform to spectrally characterize “multipulse soliton complexes” in a dissipative soliton fiber laser operating in the soliton-similariton regime. These multipulse complexes consist of two or more circulating dissipative solitons of picosecond duration, but with temporal separations of ∼5–40 ns, three orders of magnitude greater than the individual pulse durations. The results we present include a multipulse complex of 9 distinct single soliton pulses with ∼10 ns separation, as well as a multipulse complex where a soliton molecule of two bound pulses separated by ∼40 ps coexists with multiple single pulses with separations of ∼30 ns. We also use the dispersive Fourier transform to characterize breathing and transition dynamics in this multipulse regime, and our results add further to the experimental characterization of the diverse range of nonlinear structures in dissipative soliton systems.