Wagner, Herbert C.Karaman, CelalAksoy, VolkanKiran, Kadri2024-06-122024-06-1220181994-4136https://doi.org/10.25849/myrmecol.news_028:025https://hdl.handle.net/20.500.14551/22547Mixed ant colonies have long fascinated biologists since they are often examples of social parasitism. From the genus Tetramorium MAYR, 1855, two types of social parasitism are well known: dulosis and inquilinism. We present a nest record from Turkey comprising workers of T. immigrans SANTSCHI, 1927, workers and a single gyne of a new species, and brood in commonly used nest chambers. We interpret the new species as a social parasite and describe it as T. aspina sp.n. Three characteristics indicate a morphological degeneration of the worker caste: Workers of T. aspina sp.n. have strongly reduced propodeal spines, larger intranest morphological variability than workers of the T. caespitum complex sensu WAGNER & al. (2017: Myrmecological News 25: 95-129), and a larger proportion of these workers have an aberrant propodeum (propodeal syndrome) compared with workers of the T. caespitum complex. The discovery of T. aspina sp.n. raises interesting questions concerning the characterization of its socially parasitic life history and its evolutionary origin.en10.25849/myrmecol.news_028:025info:eu-repo/semantics/closedAccessMorphometricsPropodeal SpineIntranest Morphological VariabilityWorker Caste DegenerationNew SpeciesTetramorium Caespitum ComplexNon-Cryptic Pavement AntTurkeyDiversificationDivergenceTaxonomyComplexTraitsTurkeyHostAntsArticle282533Q1WOS:0004552520000022-s2.0-85068325243Q1