Aquí os dejo lo poco que he encontrado (ambas descritas por Nielsen): "Two new species of the genus Melanorivulus are described, both belonging to the Melanorivulus zygonectes species group. Melanorivulus canesi n. sp. is found at a tributary of the middle Rio Xingu basin, Pará, state of Brazil. It differs from the other species of the Melanorivulus zygonectes species group by its color pattern, with males presenting metallic green color at body sides. Melanorivulus britzkei n.sp. is found at a tributary of the right bank in the middle Rio Tapajós basin, Pará state, Brazil. It differs from the other species of the Melanorivulus zygonectes species group by males presenting a yellow metallic color pattern in the head and by a white pelvic fin. A key to the species belonging to the Melanorivulus zygonectes species group is presented".
Saludos
