The ontogenetic aspects of larvae of Hypophthalmus edentatus (Spix, 1829) from the ichthyoplankton samples collected in the Itaipu reservoir between March 1988 and April 1990 were analysed. Sample were caught by 0.5 mm mesh conic-cylindrical plankton net. Larvae of H. edentatus were identified and described as Siluriforms from the morphological and morphometric development series. They have a small to medium-sized head, long body, small eyes, little pigmentation, mandibular barbules and 53 to 56 myomeres. High values obtained with correlation coefficient (r > 0.97; p < 0.001) show that growth was proportional in different parts of the body.
Hypophthalmus edentatus; fish larvae; Itaipu reservoir; larval development; Paraná River