A revision of the ant genus Acanthostichus (Hymenoptera: Formicidae)

The genus Acanthostichus is found exclusively in the New World and consists of predominantly subterranean, predaceous ants that are rarely collected. Eleven new species are described, of a total of 22 species in the genus. Keys are provided for the workers and males. The new species and species with synonyms include:Acanthostichus arizonensis new species of USA (south eastern Arizona), A. bentoni new species of Brazil (Amazonas and Mate Grosso), A. brevicornis Emery of Guiana, Brazil and Argentina, A. brevinodis new species of central eastern Brazil, A. concavinodis new species of Bolivia, A. emmae new species of Mexico (Oaxaca?), A. femoralis Kusnezov of Argentina and Brazil, A. flexuosus new species of southern Brazil, A. fuscipennis Emery of Colombia, Ecuador, Venezuela and Brazil, A. kirbyi Emery of Peru, Brazil and Bolivia south to Argentina, A. laevigatus new species of Venezuela, A. laticornis Forel (= A. laticornis var. obscuridens Bruch) of Brazil, Uruguay, Paraguay and Argentina, A. lattkei new species of Venezuela, A. punctiscapus new species of USA (New Mexico), A. quadratus Emery (= A. serratulus var. niger Santschi new syn.) of Ecuador south to Argentina, A. quirozi new species of Mexico (Vera Cruz), A. sanchezorum MacKay of Colombia, A. serratulus (F. Smith) of Argentina and Brazil, A. skwarrae Wheeler of Mexico (Vera Cruz), A. texanus Forel (= Ctenopyga townsendi Ashmead) of USA (southern Texas) and Mexico (Nuevo Leon) and A. truncatus new species of Colombia. A species based on fossils also exists. The genus Ctenopyga is synonymized with Acanthostichus.