Redescription of Eurhopalothrix reichenspergeri (Santschi, 1923) stat. rev. (Hymenoptera: Formicidae), a Brazilian Atlantic Forest endemic species.

Eurhopalothrix reichenspergeri (Santschi, 1923) stat. rev. is resurrected from synonymy with E. gravis (Mann, 1922). In Brown Kempfs tribal basicerotine revision of 1960, Rhopalothrix reichenspergeri was transferred to the genus Eurhopalothrix and synonymized into the species E. gravis. Eurhopalothrix gravis became, from that moment until now, the species with the largest distribution in the genus. After the present work, E. gravis has a Central American and north South American (Colombia) distribution, while E. reichenspergeri is restricted to the Brazilian Atlantic Forest. A key to the workers of the southern South American Eurhopalothrix species is provided. The male of E. reichenspergeri is described and compared to the male of E. gravis, E. floridana Brown Kempf, 1960 and the putative male of E. spectabilis Kempf, 1962.