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Abstract: The Palaearctic members of the Formica rufibarbis Fabricius, 1793 group were investigated by means of numeric morphology-based alpha-taxonomy (NUMOBAT). 496 nest samples comprising 1753 worker individuals were analysed in eighteen phenotypic characters and a further 330 samples for only ten characters. Nine morphospecies and one subspecies were recognised: Formica rufibarbis, F. cunicularia Latreille, 1798, F. clara Forel, 1886, F. clara sinae Emery, 1925 stat.n., F. glabridorsis Santschi, 1925, F. orangea sp.n., F. tarimica sp.n., F. anatolica sp.n., F. tianshanica sp.n., and F. persica sp.n. All nine morphospecies were convincingly separable from each other by discriminant analysis (DA) with an error prediction by a leave-one-out cross-validation of 0.4% in the worst case. Type samples of fourteen taxa were available and positioned near to the cluster centres with a-posteriori probabilities of p > 0.998 with exception of F. clara sinae Emery, 1925 stat.n. allocated to F. clara with only p = 0.929. As a consequence, the following synonymisations were stated: F. fusca var. cinereorufibarbis Forel, 1874 as synonym of F. rufibarbis (sensu Bernard 1967), F. fusca var. rubescens Forel, 1904 as synonym of F. cunicularia (sensu Yarrow 1954) and F. cunicularia fuscoides Dlussky, 1967 as synonym of F. cunicularia (sensu Arakelian 1994), F. lusatica Seifert, 1997 as synonym and F. rufibarbis var. sinae Emery, 1925 as subspecies of F. clara. Neotypes of F. rufibarbis and F. cunicularia were fixed. A deviating population of F. tianshanica sp.n. in the Nw Chinese Bogda Shan Mountains, treated in this paper as intraspecific gyne polymorphism, may represent a cryptic species. Extension of sampling and integration of Dna analysis into the study are needed to decide this question. All species are depicted and a simplified identification key is given. Two species seem to be endemic: F. anatolica sp.n. is restricted to the south Anatolian Taurus Mountains and F. persica sp.n. to the north Iranian Elburs Mountains. These two species are also ecologically remarkable by frequently living in woodland while the other seven species preferentially occur in sun-exposed open land ranging from semi-dry grassland to semi-desert.