On the structure of periodic groups saturated by semidihedral groups

Let $\mathfrak R$ be a set of finite groups. A group $G$ is said to be saturated by $\mathfrak R$, if every finite subgroup of $G$ is contained in a subgroup isomorphic to a group from $\mathfrak R$. We prove that a periodic group saturated by the set consisting of the semidihedral group is locally finite.