Capim basin

The julii cory, Hoplisoma julii, long known as Corydoras julii, is an armoured catfish from coastal river systems south of the Amazon delta in northeastern Brazil. Also known as 'leopard cory' or 'three-lined cory', it is often confused with H. trilineatum from the upper Amazon, and many fish traded as C. julii are that species. H. julii has numerous small, distinct spots on the head, where H. trilineatum has vermiform markings, though some H. trilineatum are spotted too.

The flag tetra, Hyphessobrycon heterorhabdus, is a characid from Pará and Maranhão states in eastern Brazil, also known as 'Belgian flag tetra'. Its name has been misapplied to similar fishes across much of the Amazon, the Orinoco and the Guianas, and the true species may reach no further upstream than the rio Tapajós. It lives almost exclusively in small, shaded forest streams called igarapés.