demonstrated that ram pressure effects can be observed over a wide range of ICM conditions. In particular, in high density environments RPS severely truncates the gas disc of L$^\star$ galaxies, while in low density environments, where moderate ram pressure is foreseen, their gas disc is clearly disturbed and bent [@RH05]. The gas discs of these galaxies can be truncated to 15-20kpc in the first 20–200Myr of RPS.

![image](ShaSS_fig1.eps){width="150mm"}

@ACCESSV identified a bright (L$>$L$^\star$) barred spiral galaxy 1Mpc from the centre of the rich cluster A3558 in the Shapley supercluster core, which is strongly affected by RPS. Integral-field spectroscopic observations revealed ongoing gas stripping in the form of one-sided extraplanar ionized gas along the full extent of the disk, simultaneously with a starburst triggered by gas compression along the leading edge of the galaxy. The galaxy is estimated to be being subjected to weak-moderate ram pressure, as defined by @RH05. This adds a piece of evidence to the fact that RPS is acting more efficiently on the galaxy interstellar medium (ISM) than previously foreseen and also outside of the cluster cores as also observed in the Virgo cluster by @CGK09. This new understanding of the RPS supports the view that this 