Alto Paraguay/ Boquerón , Alto Paraná , Amambay, Caaguazú , Canindeyú , Central, Concepcion, Cordillera, Guairá , Itapúa , Misiones, Ñeembucú , Paraguarí , San Pedro, “Paraguay” (s. loc.) (ALWC, BMNH, IFML, INBP, MCSN, MCZC, MZSP, NHMB, PSWC). Literature records: Caaguazú , Central, Cordillera, “Paraguay”(s. loc.) (Emery 1890b, Emery 1896b, Forel 1907d, Forel 1908b, Forel 1909, Fowler 1981, Santschi 1916, Santschi 1934 [as “ atrinodis ”]).
Formica gracilis Fabricius 1804: 405.
Leptalea gracilis (Fabricius) . Erichson 1839: 309.
Pseudomyrma gracilis (Fabricius) . Roger 1862b: 289.
Pseudomyrma (Clavanoda) gracilis (Fabricius) . Enzmann 1944: 61.
Pseudomyrma gracilis var. atrinoda Santschi 1934: 26. NEW SYNONYMY . [ holotype w examined, NHMB ; Rio Negro , Paraná , Brazil ( Reichensperger )] .
Pseudomyrmex gracilis (Fabricius) . Kusnezov 1953: 214.
Pseudomyrmex gracilis var. atrinoda (Santschi) . Kempf 1958: 434.
Pseudomyrmex gracilis var. atrinodus (Santschi) . Kempf 1972: 219.
Ants in the Pseudomyrmex gracilis species complex are ubiquitous in the neotropics, and the species P. gracilis itself presents a confusing array of variation (Ward 1989). Santschi distinguished his variety P. atrinodus on the basis of small size and light coloration on parts of the mesosoma, but I have examined the type material and in both these characters P. atrinodus is well within the normal range of variation of the species. Phil Ward, who is revising Pseudomyrmex , concurs with this synonymy (Ward, pers comm.)
