title: Reproductive strategies in two inseminating species of Glandulocaudini, Mimagoniates microlepis and Mimagoniates rheocharis (Characiformes: Characidae: Stevardiinae).
abstract: The reproductive biology of two inseminating Glandulocaudini species, Mimagoniates microlepis and Mimagoniates rheocharis, was investigated and compared with reproductive patterns described for other inseminating and non-inseminating characids, hypothesizing the evolutionary history of these reproductive traits. The long reproductive period, with higher activity in colder months, distinguishes the reproductive strategy of these species when compared with most characiforms. The M. rheocharis population was structured in two groups of males throughout the year, mature males with high gonado-somatic index (IG  = 2·0 and 4·4) and immature and maturing males with low IG values (0·0 and 1·2). Mimagoniates rheocharis and M. microlepis showed the lowest absolute mean fecundities known for characids, indicating that inseminating species allocate less energy to oocyte production and reinforcing the hypothesis that insemination has an adaptive advantage, which provides a higher chance of fertilization.
authors.affiliation: Setor de Ictiologia, Museu de Ciências Naturais, Fundação Zoobotânica RS, Av. Dr. Salvador França, 1427, 90690-000, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: M A
authors.initials: MA
authors.lastname: Azevedo
authors.affiliation: Laboratório de Ictiologia, Departamento de Zoologia, PPG Biologia Animal, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9500, 91501970, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: C B
authors.initials: CB
authors.lastname: Fialho
authors.affiliation: Laboratório de Ictiologia, Departamento de Zoologia, PPG Biologia Animal, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves, 9500, 91501970, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: L R
authors.initials: LR
authors.lastname: Malabarba
mesh_terms: D000818:Animals; D060126:Characidae / Q000502:physiology*; D005260:Female; D005298:Fertility; D007314:Insemination; D008297:Male; D009865:Oocytes; D012098:Reproduction; D012726:Sexual Behavior, Animal
keywords: adaptive advantage; fecundity; life history; reproductive period; seasonality