Two new species of Metachromadora are described from Bananal and Bica beaches in Guanabara Bay on the coast of Rio de Janeiro, Brazil. Both new species belong to the subgenus Bradylaimus, which is characterized by the absence of lateral alae. Metachromadora prepapillata sp. nov. is characterized by the presence of 8–9 precloacal papilliform supplements, while Metachromadora verae sp. nov. is characterized by the sexual dimorphism of the amphidial fovea, presence of 8–9 precloacal tubuliform supplements, and three postcloacal papillae. An updated dichotomous key to species of Metachromadora is proposed. Metachromadora asupplementa is reinstated as a valid species.