Abstract: The inquiline ant Myrmica myrmicoxena Forel, 1895 had not been found since its first discovery from the Alp Anzeindaz (Switzerland) in 1869. Two new sites have been discovered in Switzerland (Eggishorn, Fiesch, 2,213 m a.s.l.) in 2009 and Northern Italy (Laas, South Tyrol, 1,700 m a.s.l.) in 2006. The species inhabits subalpine, short-turfed grassland. Myrmica lobulicornis Nylander, 1857 seems to be the main and probably exclusive host species, which is supported by field data and vertical distribution. Morphometric data from all three sites of M. myrmicoxena are presented and compared. There exists no obvious morphological difference between the material from the locus typicus and the specimens from the two new sites.