The Madagascan endemic myrmicine ants related to Eutetramorium (Hymenoptera: Formicidae): taxonomy of the genera Eutetramorium Emery, Malagidris nom. n., Myrmisaraka gen. n., Royidris gen. n., and Vitsika gen. n.

The monophyletic group of myrmicine ant genera related to Eutetramorium is described and its taxonomy is documented. The group is endemic in Madagascar and contains five genera: Eutetramorium Emery, 1899 (3 species, 1 of which is new); Malagidris nom. n., a replacement name for Brunella Forel, 1917, junior homonym of Brunella Smith, G.W. 1909 (Crustacea) (6 species, 5 of which are new); Myrmisaraka gen. n. (2 species, both new); Royidris gen. n. (15 species, 11 of which are new); Vitsika gen. n. (14 species, all of which are new). Keys to the worker caste are provided for all genera, and provisional keys to known males are given for Malagidris and Vitsika.