And more about the morphological evolution of the Tetramorium caespitum complex.

You know them from Wagner, H. C.; Arthofer, W.; Seifert, B.; Muster, C.; Steiner, F. M.; Schlick-Steiner, B. C. 2017. Light at the end of the tunnel: Integrative taxonomy delimits cryptic species in the Tetramorium caespitum complex (Hymenoptera: Formicidae). Myrmecological News 25:95–129. or http://antcat.org/documents/67…ium_caespitum_complex.pdf

But there is more:

http://www.nature.com/articles/s41598-018-30890-z
http://www.nature.com/articles/s41598-018-30890-z.pdf
https://static-content.springe…2018_30890_MOESM1_ESM.pdf