Aspectos reproductivos de<i>Trichomycterus areolatus</i>Valenciennes, 1846 (Pisces: Teleostei: Siluriformes) en Rio Angostura, Chile

Abstract

Major aspects of the breeding biology of Trichomycterus areolatus (Siluriformes, Trichomycteridae) were studied from collections and observations made at Rio Angostura, Area Metropolitana. Individuals over 25 mm total length were found the whole year, whereas smaller individuals were found between September and May only. Males are more numerous than females. Individuals of this species are not sexually dimorphic. The minimum length of mature fishes was 56.7 mm for males and 51.1 for females which corresponds to about the half of the maximum length which the species reaches. During spawning (September to December) the mature ovocytes look bright yellow and their diameter ranges from 1,51 to 2,1 mm. Trichomycterus areolatus has an asynchronous development of the ovocytes; ovocytes in different stages of development are always found in mature ovaries which indicates that females have more than one spawning during breeding season.