  We examine the role of shape of dynamical heterogeneities on the validity of
the Stokes-Einstein (SE) and Stokes-Einstein-Debye (SED) relations in
quasi-two-dimensional suspensions of colloidal ellipsoids. For ellipsoids with
repulsive interactions, although the orientational relaxation time remains
coupled to the structural one, the SED relation by the Einstein formalism shows
a breakdown. Strikingly, we find that it is the change in the shape of the
dynamical heterogeneities from string-like to compact and not just their
presence that results in the breakdown of both the SE and SED relations. On
introducing a short-range depletion attraction between the ellipsoids,
associated with the lack of morphological evolution of dynamical
heterogeneities, the SE and SED relations remain valid even for deep
supercooling. Our observations are consistent with numerical predictions.
