  We pursue the study of a model convex functional with orthotropic structure
and nonstandard growth conditions, this time focusing on the sub-quadratic
case. We prove that bounded local minimizers are locally Lipschitz. No
restriction on the ratio between the highest and the lowest growth rates are
needed. The result holds also in presence of a non-autonomous lower order term,
under sharp integrability assumptions. Finally, we prove higher
differentiability of bounded local minimizers, as well.
