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tokens: The initial sample contains 777 spectroscopically unobserved SuperWASP/ ROSAT objects, with rotation periods ≲ 5 d, declinations >−20°, 8 V 15 and spectral-types FGK, corresponding to 0.7 V − K s 3.8. Targets in the first list are selected from the parent sample. A second list comprised of a subset of 160 targets whose proper motions and positions are compatible with membership of the Pisces MG. B and V photometry for all targets was sourced from the catalogue that provides the smallest errors: APASS DR9 (Henden et al. 2016 ), UCAC4 (Zacharias et al. 2013 ) or NOMAD (Zacharias et al. 2005 ). All K s photometry is from 2-Micron All-Sky Survey (2MASS; Cutri et al. 2003 ). 2.1 Selecting potentially young stars in superWASP We learned from BJM15 that the majority of the raw light curves of young stars exhibited irregular features as well as sinusoidal behaviour, indicative of star-spot modulation and/or chromospheric plages – both prognostic of stellar youth. We not only assigned priority to any objects whose light curves displayed any of these features but also demanded clean light curves and consistent rotation period measurements over several seasons of observations. We also tried to screen out, through manual inspection of the light curves, targets that looked like eclipsing binaries. The reader is referred to section 2 of BJM15 for a description of the SuperWASP project and post-processing techniques used to measure rotation periods, which are identical to those carried out in this work. Table 1 shows the details of the period measurements for the sample of likely-young and single objects in our sample, which are defined in Section 5.7 . Fig. 1 displays rotation periods as a function of V − K s colour for our entire observed sample. Details for the other observed targets are provided online. We obtained spectroscopy for 122 stars, 103 selected from the criteria described here, and a further 19 satisfy these criteria, but have proper motions consistent with membership of the Pisces MG (see the next section). Figure 1. Rotation periods and V − K s colour for the entire sample observed in this paper. Red squares represent 17 objects that were identified to be likely-young stars and were considered likely-single (referred to as the ‘likely-young sample’, see Section 5.7 ). These objects are labelled from 1 to 17 and their corresponding SuperWASP names are provided in Table 1 . Any objects that had two or more separate radial velocity measurements whose mean values varied by more than 2 error bars from each other were assumed to be short-period binaries (see Section 4.2 ) and are denoted here by open green circles. All other objects are shown with filled green diamonds. This symbol scheme is used throughout this work, unless otherwise stated. The various lines represent the I- and C-sequence gyrochrones proposed by Barnes ( 2003 ) and calibrated by Mamajek Hillenbrand ( 2008 ), plotted at a range of ages. Table 1. Measured periods for the