  In the semiclassical limit of open ballistic quantum systems, we demonstrate
the emergence of instantaneous decay modes guided by classical escape faster
than the Ehrenfest time. The decay time of the associated quasi-bound states is
smaller than the classical time of flight. The remaining long-lived quasi-bound
states obey random-matrix statistics, renormalized in compliance with the
recently proposed fractal Weyl law for open systems [W. T. Lu, S. Sridhar, and
M. Zworski, Phys. Rev. Lett. 91, 154101 (2003)]. We validate our theory
numerically for a model system, the open kicked rotator.
