The possible existence of a ($ sbar s$) S = 0 meson at M $approx$ 762 MeV is discussed through a critical analysis of the existing data. Different experimental results are considered and show the possibility that the presence of such meson is not exc
luded by the data, but may be hidden by more excited mesons at nearby masses.
New data of narrow low mass unflavoured mesonic structures are presented. A table of these exotic masses is obtained adding previously published data. The mass sequence shows a significant coupling of some of these clusters with stable hadrons: pion,
nucleon, and deuteron. Indeed this coupling allows to reproduce rather well the masses of exotic narrow baryons and dibaryons. A discussion is presented to suggest a possible interpretation of these exotic hadronic structures.
