Chrysoctonoides longisetosa Huber & Triapitsyn ( Hymenoptera : Mymaridae ), gen. n. and sp. n., is described from Australia. It is compared with the related genus Chrysoctonus , known from Africa and the New World. Myrmecomymar Yoshimoto, syn. n., is synonymized under Chrysoctonus Mathot and its type species is transferred to Chrysoctonus as Chrysoctonus masneri (Yoshimoto), comb. n.