Distribution versus V−K_s color of the rotation periods of the β Pictoris bona fide members that are either single (21 stars) or wide (ρ> 500 AU) components of binary or multiple systems (14 stars). The meaning of the symbols is given in the legend. The solid line is a polynomial fit to the rotation periods. Dotted lines represent the ±3σ standard deviation of the residuals with respect to the fit.