A new species of the spider genus Actinopus Perty from Cochabamba, Bolivia is described under the name of Actinopus cochabamba sp. n. This is the second species of the genus described for the country. Detailed morphological description and illustrations of the new species are presented.

Se describe una nueva especie de araña del género Actinopus Perty de Cochabamba, Bolivia bajo el nombre Actinopus cochabamba sp. n. Esta es la segunda especie del género descripta para el país. Se presenta una detallada descripción morfológica e ilustraciones de la nueva especie.

The Neotropical Sasoninae Neodiplothele Mello-Leitão, 1917 is revised and now includes eight species. Neodiplothele can be distinguished from other Sasoninae by the absence of the posterior median spinnerets and differs Neotropical relatives as Cosmopelma by the absence of cuspules on coxae of leg I and Paracenobiopelma by the absence of cuspules on the labium. The male of N. irregularis Mello-Leitão, 1917 and N. picta Vellard, 1924 are described and illustrated for the first time. Neodiplothele leonardosi Mello-Leitão, 1939 is considered a junior synonym of N. irregularis. Five new species are described from Brazil: N. aureus sp. nov. from the states of Ceará, Rio Grande do Norte, Paraíba, and Minas Gerais, N. itabaiana sp. nov. from Sergipe, N. martinsi sp. nov. from Bahia, Espírito Santo, and Minas Gerais, N. indicattii sp. nov. from Espírito Santo, Minas Gerais, Rio de Janeiro, and São Paulo, N. caucaia sp. nov. from Ceará, Goiás, and Mato Grosso do Sul. Two informal groups are proposed based on genitalia morphology: irregularis group and picta group. An identification key and new distribution records for all known species are given.