In this study, 10 nominal species of Eustala Simon, 1895 are synonymized with other species of the genus, mostly based on matching males and females erroneously described as different species. Parawixia rimosa (Keyserling, 1892) is considered a senior synonym of Eustala decemtuberculata Caporiacco, 1955. Eustala isosceles Mello-Leitão, 1939 is transferred to Kapogea Levi, 1997 and considered a senior synonym of Kapogea alayoi (Archer, 1958) based on abdomen shape and coloration. Micrathena beta Caporiacco, 1947 is redescribed, illustrated and transferred from Linyphiidae back to Araneidae. This species can be easily distinguished from other members of the genus by the male palpus with an enlarged and modified paracymbium and a narrower hook as a conductor. Micrathena sanctispiritus Brignoli, 1983 is removed from the synonymy with M. lindenbergi Mello-Leitão, 1940 and considered a senior synonym of M. guanabara Levi, 1985.

A new species of Argiope Audouin, 1826 is described. This is a large Argiope from South America and is found mainly in "cerrado" vegetation in central Brazil. Argiope legionis sp. nov. is most similar to A. ericae LEVI, 2004 but differs from this species by the coloration and epigynum in the female and the median apophysis and embolus of the palpus in the male palp.