Corbet diagram for a large sample of HMXBs taken from Fortin et al. (2023). Blue circles represent BeX. Orange squares are (supergiant) wind accretors, while maroon circles are Roche-lobe overflow systems. The two BeX with anomalous positions, namely SAX J2103.5+4545 and 1A 1118−615, are represented by larger striped blue circles. The intermediate position of X 0726−260 is displayed by the green diamond.