title: Evidence for hermaphroditism in the Squalius alburnoides allopolyploid fish complex.
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.
authors.affiliation: Faculdade de Ciências, Centro de Biologia Ambiental, Universidade de Lisboa, Lisboa, Portugal. immatos@fc.ul.pt
authors.forename: Isa
authors.initials: I
authors.lastname: Matos
authors.forename: M P
authors.initials: MP
authors.lastname: Machado
authors.forename: E
authors.initials: E
authors.lastname: Sucena
authors.forename: M J
authors.initials: MJ
authors.lastname: Collares-Pereira
authors.forename: M
authors.initials: M
authors.lastname: Schartl
authors.forename: M M
authors.initials: MM
authors.lastname: Coelho
mesh_terms: D000818:Animals; D012734:Disorders of Sex Development / Q000503:physiopathology*; D005260:Female; D005399:Fishes / Q000502:physiology*; D006066:Gonads / Q000502:physiology*; D008297:Male; D008853:Microscopy