Reproductive biology of Neotropical tetra fish Mimagoniates lateralis (Nichols, 1913) (Characiformes, Characidae), an endangered species of blackwater streams of southeastern Brazil

Abstract

ABSTRACT This study provides for the first time information about the reproductive biology of Mimagoniates lateralis, an endangered species of inseminating Neotropical tetra that occurs in blackwater streams of southeastern Brazil. We analyzed 404 individuals, of which 214 were females, 117 were males, and 73 were immature juveniles. The sex ratio was 1.83 females/males. Males were larger than females. The estimated size at first maturation for females was 22.2 mm SL, and for males 23.4 mm SL. We also analyzed 94 ovaries from mature females, and the estimated absolute fecundity was 116.37 ± 26.68 oocytes, the oocyte diameter varying from 0.1 to 1.0 mm. The spawning type was classified as multiple, with two modal values corresponding to different oocyte lots. These data contribute to substantiate future assessments of the conservation status of M. lateralis, as well as future attempts to guarantee the preservation of this species and its natural habitat.