(a) Same as panel (b) of Fig. 5, but MSd stars are also removed. The remaining stars, constituting the MSe population, form a well-defined sequence on this plane, which we select and further refine in panels (b) and (c). (d)-(f) Fiducials (in green) used to verticalise the MSe sequences. (e)-(g) Verticalised CMDs. (h)-(i) TpCD and the Hess diagram of MSe stars. (l) We identified the two MSe populations as MSe1 (lime) and MSe2 (green).