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Updated: Jun 12, 2026

Dissection of Larval Zebrafish Gonadal Tissue
Published on: April 26, 2017
Evidence for hermaphroditism in the Squalius alburnoides allopolyploid fish complex
Isa Matos1, M P Machado, E Sucena
1Faculdade de Ciências, Centro de Biologia Ambiental, Universidade de Lisboa, Lisboa, Portugal. immatos@fc.ul.pt
Abstract:
Fish show an amazing variety of mechanisms of sex determination and modes of reproduction. Of these, simultaneous hermaphroditism has rarely been described. Here, we report a novel case of this phenomenon in adults of the Squalius alburnoides allopolyploid cyprinid complex. We found evidence for the simultaneous presence of mature male and female gonads on the basis of gonad gross morphology and histological analyses. Different stages of male and female germ cell maturation were identified, including motile spermatocytes. We hypothesize on the genetic and/or environmental causes of this phenomenon.
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