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 breviceps sp. nov. ( Fig. 4 B and Fig. 6 F) Derivation of the name. Breviceps is the Latin expression for “with a short head”. Holotype . SMF MeI 2305 (Ƥ). Paratypes ( ƤƤ ) . SMF MeI 11054, MeI 13151. Type locality and horizon. Grube Messel, Hesse, Germany . Messel formation, middle Eocene, ca. 47 Ma ( Mertz & Renne 2005 ). Description. Gyne. BL 7–9 mm . Head subrectangular, about 1.1 times longer than wide, with feebly concave posterior margin and rounded posterolateral corners. Anterior clypeal margin projected as rounded lobe. Eyes ovate, comparatively small. Head about 3.5 times longer than maximum eye diameter and scape length. Funicular joints shorter than thick. Mandible massive, triangulate. Forewing with closed cells 1+2r, 3r , and mcu . Cell mcu rhomboidal. Vein sections RS and M with joint start from cell 1+2r (section RS+M practically absent). Coloration completely preserved only in paratype MeI 11054. Posterior part of head and most part of mesosoma yellowish brown, anterior part of head, spot near ocelli, and median parts of gastral tergites dark brown. Coloration of holotype gaster as in MeI 11054. Whole body of paratype MeI 13151 black, but probably coloration was changed during diagenesis. Wings of all specimens uniformly smoky brown, with darker veins and pterostigma. Measurements (in mm). Holotype MeI 2305: BL 9.2, AL 2.6, HL 1.6, HW 1.5, ED 0.46, FWL 5.1; paratype MeI 11054: BL 7.2, AL 2.1, ED 0.40, FWL 5.1; paratype MeI 13151: BL 7.1, AL 1.85, FWL 4.3.