Reproductive biology of Triportheus trifurcatus (Castelnau, 1855) (Characiformes: Characidae) in the middle rio Araguaia, MT, Brazil

Abstract

The study of the reproductive biology of Triportheus trifurcatus of the middle rio Araguaia was carried out using 275 specimens obtained in seven collections conducted in the period between November 2003 and January 2005. Females prevailed among the classes of intermediate length, as well as in the total number of samples. On the other hand, males prevailed in the smaller classes. The average length of females was larger than that of males. Four stages of gonadal maturation were macro- and microscopically identified: B - maturation, C - mature, D - spent and E - resting. Stage A (immature) was not found in the habitats sampled. The smallest-length male was 110 mm in standard length, and the smallest female, 119 mm. The spawning period occurred from November to January, with reproductive peak in December/January, coinciding with the highest water levels. The absolute fecundity is considered low, and there is a positive correlation between fecundity and gonad weight, body weight and standard length. Food ingestion during the reproductive period did not suffer any interference, and it is suggested complete spawning for this species.<br>A biologia reprodutiva de Triportheus trifurcatus, do médio rio Araguaia, é estudada com base em 275 exemplares obtidos em sete coletas, realizadas no período de Novembro/2003 a Janeiro/2005. Nas classes de comprimento intermediário e na amostragem geral, as fêmeas predominam, mas nas classes menores prevalecem os machos. As fêmeas se apresentam, na média, maiores que os machos. Quatro estádios de maturação gonadal são identificados, macro e microscopicamente: B- maturação, C- maduro, D-esgotado/ espermiado e E- repouso. O estádio A (imaturo) não foi registrado nos biótopos amostrados. O menor exemplar macho maduro apresenta 110 mm e a menor fêmea 119 mm de comprimento padrão. O período de desova ocorre de Novembro a Janeiro, com pico reprodutivo em Dezembro/Janeiro coincidindo com os níveis mais elevados das águas. A fecundidade absoluta é considerada baixa e há correlação positiva entre fecundidade e peso das gônadas, peso corporal e comprimento padrão. A ingestão de alimento não sofre interferência durante o período reprodutivo e é sugerida desova total para a espécie em estudo

Species‐level ichthyoplankton dynamics for 97 fishes in two major river basins of the Amazon using quantitative metabarcoding

“…Nevertheless, they reported that all Triportheus species, which are considered to be the same as in the upper Amazon in our sampling area, spawned at the same period of the year, mainly during the flooding season. A fourth species, Triportheus trifurcatus , studied in the Araguaia River, Tocantins basin in Brazil, also indicated a reproductive season between November and January during the flooding period (Martins‐Queiroz et al, 2008), similar to the other species in the Tocantins and to Triportheus angulatus and Triportheus auritus in our study. The reason why Triportheus albus would have an inverse phenology in the Peruvian Amazon is beyond the scope of the present study, but emphasizes the potential of our barcoding approach for investigating the spawning patterns of Amazonian fishes.…”

Biologia reprodutiva de Astyanax henseli (Teleostei, Characidae) do curso superior do Rio dos Sinos, RS, Brasil

“…Para peixes das regiões tropicais do Brasil, onde o nível fluviométrico dos rios determina a disponibilidade de hábitats e de alimento, as chuvas parecem ser o fator que mais influencia os ciclos reprodutivos, como encontrado em muitos trabalhos (SILVANO et al, 2003;ANDRADE & BRAGA, 2005;MARTINS-QUEIROZ et al, 2008;COSTA & MATEUS, 2009;SANTOS et al, 2010;OLIVEIRA et al, 2010). Em regiões sub-tropicais, no entanto, o período reprodutivo dos peixes parece ser influenciado mais pela temperatura do que pelas chuvas (VAZZOLER & MENEZES, 1992).…”

Reproductive strategy of Psectrogaster rhomboides Eigenmann & Eigenmann, 1889, a freshwater fish from Northeastern Brazil

“…The reproductive period of P. rhomboides occurred during the rainy season, as is the case with P. amazônica , where the peak of breeding activity is November to January, in the high water levels of the rainy season (Martins‐Queiroz et al., ).…”