M_r vs. (NUV − r) colour-magnitude diagram of the three loose groups: the NGC 5018 group (orange points), the NGC 1533 triplet (mauve points), and the IC 1459 group (teal points). The Wyder et al. (2007) fits (dashed lines) and the error estimations (solid lines) for the Red Sequence (red lines) and Blue Cloud (blue lines) are shown. Open circles mark early-type galaxies (ETGs), filled circles mark the BGGs, and filled squares mark LTGs. The NUV data are from NED, while the r band data for the NGC 5018 group are from Spavone et al. (2018), the data for the NGC 1533 triplet are from Cattapan et al. (2019), and the data for the IC 1459 group are presented in this work.