Wagner, H.C., Karaman, C., Aksoy, V. & Kiran, K.

A mixed colony of Tetramorium immigrans Santschi, 1927 and the putative social parasite Tetramorium aspina sp.n. (Hymenoptera: Formicidae)

Mixed 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 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 raises interesting questions concerning the characterization of its socially parasitic life history and its evolutionary origin.

Open access, licensed under CC BY 4.0. © 2018 The Author(s).