Distribution and first insight into the reproductive biology of two species of the genus Rhamdia (Siluriformes, Heptapteridae) in a Biosphere Reserve
Distribution data and reproductive biology of freshwater catfishes of the genus Rhamdia remain insufficiently explored, limiting our knowledge of these ecologically, nutritionally, and economically important species. We provide updated distribution data and a preliminary study of the reproductive biology of the Pale catfish, Rhamdia guatemalensis, and the Filespin chulín, Rhamdia laticauda in the Tehuacán-Cuicatlán Biosphere Reserve (TCBR), Oaxaca, Mexico, based on vouchered records and analyses of sex ratio, sexual size dimorphism, size at first gonadal maturation, and total fecundity. Specimens were collected from 20 sites within the TCBR using electrofishing during two periods, 2006–2007 and 2015–2016. The Pale catfish was recorded in eight municipalities, whereas the Filespin chulín occurred in five, with a similar elevation range. Both species exhibited an overall sex ratio of 1:1 and female-biased sexual dimorphism in standard length (SL) and body mass (BM). Size at first sexual maturity was estimated at 97.6 mm SL in R. guatemalensis and 79 mm SL in R. laticauda. Both species exhibited high fecundity, with mean numbers of eggs per female of 9647 for the Pale catfish (n = 13) and 1457 for the Filespin chulín (n = 11). Fecundity was positively correlated with ovary weight in both species. Our results contribute to the understanding of the distribution and reproductive biology of native freshwater catfishes in the TCBR.
Found an error? Please report to login@optimap.science.