Imparfinis, Eigenmann & Norris, 1900

Ota, Renata Rúbia, Deprá, Gabriel de Carvalho, Graça, Weferson Júnio da & Pavanelli, Carla Simone, 2018, Peixes da planície de inundação do alto rio Paraná e áreas adjacentes: revised, annotated and updated, Neotropical Ichthyology 16 (2), pp. 1-111 : 67-68

Imparfinis

1. Body very elongate; adipose-fin base very long, extending to caudal fin, its length about half the stardard length, several times longer than anal-fin base; head depressed.............................................................. I. borodini

1’. Body not elongate; adipose-fin base short, not extending to caudal fin, its length contained several times in stardard length, about the same as that of anal-fin base; head not depressed .............................................................. 2

2. Dark-brown inconspicuous longitudinal band along flank; first dorsal-fin ray approximately the same size as the second................................................................. I. mirini

2’. Dark-brown conspicuous longitudinal band along flank; first dorsal-fin ray shorter than the second............... ............................................................................. I. schubarti