The ant genus Myrmecina, whose diversity is mostly concentrated in SE-Asia and Oceania, counts four W-Palearctic species. The extremely euryecious and well-studied Myrmecina graminicola occurs from Iberia to the Caucasus and from the Maghreb to Scandinavia, while three little-known species (M. atlantis, M. melonii and M. sicula) coexist with M. graminicola in their narrow Maghrebian, Sardinian and Sicilian ranges, respectively. Myrmecina sicula has been described about 140 years ago from a single site and two specimens only. Their unique morphology suggested the validity of this taxon ever since, but no additional specimens were found in the following century. We present the results of decades of sampling efforts across Sicily, resulting in the collection of M. graminicola from 70 sites and M. sicula from 13 sites. We confirm M. sicula unique morphological identity and report on the marked distributional and ecological differences between the two species. Myrmecina graminicola is widespread and inhabits diverse, mainly forested habitats from lowland to high mountain sites, while M. sicula was found in a very narrow region of old carbonate platform between NW-Sicily and the Egadi Islands, mostly in sparsely vegetated sites at mid to low-altitude. Reviewing their common morphological and biogeographic traits, we propose to consider M. atlantis, M. melonii and M. sicula as a distinct M. sicula complex, whose identity and history deserves further investigation through molecular analyses.