$S$ wave hidden charm - hidden strangeness production in $e^+e^-$ annihilation
It is suggested that the recently observed enhancement of the relative yield in $e^+e^-$ annihilation of states with hidden charm and hidden strangeness above 4.43\,GeV is associated with the $S$ wave production of the charmed strange meson pairs $D_{s0}(2317) \bar D_s^* + {\rm c.c.}$ and $D_{s1}^*(2460) \bar D_s+ {\rm c.c.}$. This mechanism implies a pattern of breaking of the Heavy Quark Spin Symmetry (HQSS) that can be tested in the final channels such as $\eta_c(1S) \phi$, $h_c(1P) \eta $, $h_c(1P) \eta' $ produced in the same energy range.