Fossil ants of the genus Gesomyrmex Mayr (Hymenoptera, Formicidae) from the Eocene of Europe and remarks on the evolution of arboreal ant communities Author Dlussky, Gennady M. Author Wappler, Torsten Author Wedmann, Sonja text Zootaxa 2009 2031 1 20 journal article 10.5281/zenodo.186261 f4bc44d8-5688-4500-839e-2449308f744c 1175-5326 186261 0919CF2B-DBC2-4504-B48A-8AD0D01695DB Gesomyrmex curiosus sp. nov. ( Fig. 4 C and Fig. 6 H) Derivation of the name. Curiosus is Latin for funny. Holotype . SMF MeI 11953 (head of Ƥ). Type locality and horizon. Grube Messel, Hesse, Germany . Messel formation, middle Eocene, ca. 47 Ma ( Mertz & Renne 2005 ). Description. Gyne. Head subtrapezoid, broader in the front than in the back, with gradually rounded posterior margin, without posterolateral corners. Anterior clypeal margin weakly projected, forms a small rounded lobe. Eyes comparatively small: head 4.4 times longer than maximum eye diameter. Frontal carinae short, divergent, reach the anterior margin of eye. Scape does not reach posterior margin of eye; head 3.5 times longer than scape. Mandible triangular, with 5 massive blunt teeth. Most part of the head brownish yellow, anterior part of head and spot near ocelli more dark, mandibles dark brown. Measurements (in mm). Holotype MeI 11953: HL 2.3, HW 1.6, SL 0.65, ED 0.52. Comments. Only the head of the unique holotype specimen is well preserved. However it is very different from all fossil and living species.