Position-velocity diagram of the NGC 4490 system. Velocities Δv_los are given relative to that of NGC 4490, and positions are in angular separation along the major axis of the system’s distribution d_major (black dashed line in Fig. 1). The positions of the two objects without available velocities are indicated with vertical yellow dashed lines. Only two quadrants are occupied by the data, consistent with a rotating satellite structure. The likely pair of dwarf galaxies is highlighted by yellow circles.