Strange hadrocharmonium

It has been recently suggested that the charged charmoniumlike resonances Z(c)(4100) and Z(c)(4200) are two states of hadrocharmonium, related by the charm quark spin symmetry in the same way as the lowest charmonium states eta(c) and J/psi. It is pointed out here that in this picture one might expect existence of their somewhat heavier strange counterparts, Z(cs), decaying to eta K-c and J/psi K. Some expected properties of such charmoniumlike strange resonances are discussed that set benchmarks for their search in the decays of the strange B-s mesons. (C) 2019 The Author. Published by Elsevier B.V.