Synopsis of the myrmecophilous genus Ecitonides Wasmann (Coleoptera, Staphylinidae, Paederinae), with description of two new species from Brazil

The Neotropical genus of myrmecophilous beetles, Ecitonides Wasmann, 1894 (Staphylinidae: Paederinae: Lathrobiini), currently includes nine valid species distributed in French Guiana, Suriname, Brazil, Peru, Paraguay, and Argentina. Members of this genus are notable for the tuberculate ornamentation on the head, thorax, and abdomen. Although little is known about the biology of these beetles, there are records of association with different species of army ants (Labidus Jurine, 1807 and Nomamyrmex Borgmeier, 1936).

In this study, a detailed comparative morphological study of all available species for study was conducted, descriptions of two new species, Ecitonides colossus sp. nov. and Ecitonides splendidus sp. nov., are provided, and lectotypes for Ecitonides brevicornis Wasmann, 1900 and Ecitonides spectabilis Borgmeier, 1932 are designated. Diagnoses, illustrations, and photographs are given; an identification key is provided for all 11 species as well as new geographic distribution data.

The aim of this study is to provide morphological data that will serve as a tool for a future investigation of the phylogenetic position of the genus and facilitate species recognition through diagnostic morphological characters and an identification key.