Colour–colour [4.6]−[12] vs. [12]−[22] diagram using WISE ALLWISE mid-IR magnitudes; see Tisserand et al. (2020, Fig. 1) for a direct comparison with known RCB stars. The new RCB star, C105, is indicated with a black dot. The new dLHdC stars are indicated with green dots and grey arrows for those published with a magnitude limit in the [22] passband. The known dLHdC stars are shown with purple dots.