Revision of Serviformica part 1

A taxonomic revision of the Palaearctic members of the Formica cinerea, F. subpilosa and F. rufibarbis species groups is provided under application of Numeric Morphology-Based Alpha-Taxonomy. Twentyfour numerically described phenotypic characters were investigated in 1,486 nest samples with 5,242 worker ants. The recorded characters included one size indicator, eleven shape variables, ten seta characters and two pigmentation characters – resulting in about 105,000 primary data. The three species groups were delimited on the basis of eight shape and one seta character. Species hypotheses were formed by exploratory data analyses which were then tested by linear discriminant analyses. The revision considered 57 Palaearctic taxa and recognized 31 valid species, 1 subspecies, 17 synonyms and 8 incertae sedis. Six species were described as new: Formica iranica n.sp., F. kirgisica n.sp. and F. superpilosa n.sp. as members of the F. subpilosa group and F. himalayensis n.sp. and F. gebaueri n.sp. as members of the F. rufibarbis group. The newly described Formica lhasaensis n.sp. from Tibet and F. rufolucida Collingwood 1962 cannot be allocated to one of the focal species groups and belong to other clades. Formica torrentium Bernard 1967, F. tombeuri Bondroit 1917, F. sinae Emery 1925 and F. lusatica Seifert 1997 were raised to species rank. Formica decipiens Bondroit 1918 is shown as junior synonym of F. tombeuri Bondroit 1917, F. cinerea italica Finzi 1928 as junior synonym of F. fuscocinerea Forel 1874 and Formica glauca Ruzsky 1896 as junior synonym of Formica clara Forel 1886. Subclusters indicated by exploratory data analyses within the main clusters of Formica cunicularia Latreille 1798 and F. subpilosa Ruzky 1902 were considered as intraspecific polymorphism. A determination key for the whole Palaearctic range is provided. Z-stack images in standard viewing positions are given for all newly described species. Interspecific hybridization is shown between Formica cinerea Mayr 1853 and F. selysi Bondroit 1918 locally in the Alps and between F. cinerea and F. balcanina Petrov & Collingwood 1993 in a hybrid zone in Romania.