We describe three new species of the earthworm genus Holoscolex from the Gurupi Biological Reserve in Maranhão state, Brazil. The Reserve, with the Indigenous Territories Awá, Caru, Alto Turiaçu and Alto Rio Guamá represent the last continuous forest remnants of the Belém Endemism Area, the most deforested and threatened area of Brazilian Amazonia. Holoscolex dossantosi sp. nov. has tubercula pubertatis looking like double bands, Holoscolex alatus sp. nov. presents alate tubercula pubertatis, and Holoscolex fernandoi sp. nov. has testis sacs and several intraclitellar atrial glands associated with genital markings between XIX and XXII. The presence of these unusual characters in Holoscolex fernandoi sp. nov. suggests that this species could be an evolutionary transitional stage linking Eudrilidae and more recent Glossoscolecidae genera.

Edessa is comprised of six subgenera, Aceratodes, Ascra, Dorypleura, Edessa, Hypoxys and Pygoda. Ascra is here elevated to genus status based on characteristics of the male and female genitalia and the gibbous pronotum. This genus is comprised of eight species previously placed in Edessa-E. bifida, E. cordifera, E. petersii, E. abdita, E. championi, E. privata, E. conspersa and E. morbosa, as well as six new species. The genus Ascra was further divided into two groups of species bifida and privata separated by a different pattern of punctuation on body and pygophore. Here we present only the bifida species group formed by A. bifida, A. cordifera, A. petersii, A. abdita, and A. championi, as well as two new species-A. vluteum and A. flavoscutellata. Lectotypes of Aceratodes sigillatus, Edessa abdita, E. championi, E. cornuta, E. densata and E. petersii are designated. Aceratodes sigillatus, Edessa cornuta, E. densata, E. picata, and E. florida are considered junior synonyms of A. bifida. Interestingly, some species of this genus are considered edible in Mexico.

Three new species of the glossoscolecid earthworm genus Righiodrilus are described from material collected in northern Pará and Maranhão States, Brazil. Rhigiodrilus gurupi n. sp. is characterized by four pairs of post-testicular spermathecae in xiv-xvii. Rhigiodrilus viseuensis n. sp. is distinguished by tubercula pubertatis in xix-xxiii and clitellum in xvi-xxiii. Rhigiodrilus moju n. sp. is the only species in the genus that lacks tubercula pubertatis. We provide an updated key and a distribution map for all species of Righiodrilus.

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