Spectroscopic Hertzsprung-Russell diagram (Langer & Kudritzki 2014, sHRD, with , for evolutionary rotating tracks adopting old (dashed) and new (solid) winds. Grey dots represent the sample of O-type stars taken from the surveys of Holgado et al. (2022). The black line represents the ZAMS for all models, and the dark yellow line represents the region close to the ZAMS in which no stars are found (Holgado et al. 2020).