RESUMO
A new species of the spider genus Cuacuba from Brazil, C. ribeira sp. nov. is described and illustrated based on eighty-six specimens collected from caves in the Vale do Ribeira region, in the states of São Paulo and Paraná. This species is recognized by the hook-shaped median apophysis on the male palp, and females by having invaginations on the sides of the median posterior edge of the epigynal plate. Cuacuba ribeira sp. nov. is the third species recorded for the genus, and like the other two, also comes from Brazilian caves.
RESUMO
Three new species of the genus Plato from caves in the states of Para and Minas Gerais, Brazil, are described. P. novalima sp. n., from Minas Gerais, is the first record of the genus in the southeastern region of Brazil. P. ferriferus sp. n. and P. striatus sp. n., from Carajas, Para, north of Brazil, are also described. The former is an extremely abundant species, whereas the latter has only one known male specimen. Cuacuba gen. n. is proposed and represented by two new species, C. mariana sp. n. (type species) and C. morrodopilar sp. n., both from the state of Minas Gerais. Morphology of genitalia in Cuacuba gen. n. is similar to other Theridiosomatidae genera and is herein discussed. None of the proposed species presents troglomorphic adaptations. They are widespread, abundant inside caves in different and large karst areas, and each genus prefers different lithologies.