Melanorivulus aithogrammus, a new miniature species (Cyprinodontiformes: Rivulidae) from lower Rio Tapajós basin, Brazil, with a key for the species of the Melanorivulus zygonectes species group
by Dalton Tavares Bressane Nielsen and Ricardo Britzke – aqua 25 (1) pp. 35-43
A new species of Melanorivulus, belonging to the Melanorivulus zygonectes species group, is described from the lower Rio Tapajós basin, Pará state, Brazil. Melanorivulus aithogrammus, new species, was recorded from a small tributary in the left bank of Rio Tapajós, Amazon basin. It differs from the other species of the Melanorivulus zygonectes species group by its color pattern in males, presenting sides of body light gray, with irregular oblique red bars, some in the shape of an inverted “Y”, caudal fin hyaline with 5-6 brownish-red vertical bars, and pointed anal fin. A key to the species belonging to the Melanorivulus zygonectes species group is presented.