title: The occurrence of spermatozoa in the ovary of the gynogenetic viviparous teleost Poecilia formosa (POECILIIDAE).
abstract: The reproductive mode of the female viviparous teleost Poecilia formosa (Poeciliidae) represents the phenomenon known as gynogenesis; that is, parthenogenetic development is initiated by spermatozoa which are needed for physiological activation of the egg and the initiation of gestation, but spermatozoa are prevented from contributing to the genome of the embryo. For the reason that no previous histological analyses of the ovary of this species during the reproductive cycle has been published the present study has been conducted. This study examined the histology of the ovary of P. formosa during nongestation and gestation phases and identified the presence of spermatozoa inside the ovary. Spermatozoa were observed in folds of the ovarian epithelium of P. formosa during both the nongestation and gestation phases. Sperm storage as documented in this study is a very important trait for the gynogenetic viviparous fish P. formosa contributing to the understanding of this species reproduction.
authors.affiliation: Departamento De Biología Comparada, Facultad De Ciencias, Laboratorio De Biología De La Reproducción, Universidad Nacional Autónoma De México, Ciudad Universitaria, DF. México, 04510, México.
authors.forename: Mari Carmen
authors.initials: MC
authors.lastname: Uribe
authors.affiliation: Department of Vertebrate Zoology, Division of Fishes, National Museum of Natural History, MRC 159, Smithsonian Institution, Washington, DC.|Florida Fish and Wildlife Conservation Commission, Florida Fish and Wildlife Research Institute, St. Petersburg, Florida.
authors.forename: Harry J
authors.initials: HJ
authors.lastname: Grier
authors.affiliation: Departamento De Biología Comparada, Facultad De Ciencias, Laboratorio De Biología De La Reproducción, Universidad Nacional Autónoma De México, Ciudad Universitaria, DF. México, 04510, México.
authors.forename: Gabino
authors.initials: G
authors.lastname: De la Rosa-Cruz
authors.affiliation: Physiological Chemistry, Biocenter, University of Würzburgand Comprehensive Cancer Center Mainfranken, University Clinic Würzburg, 97074, Würzburg, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Schartl
mesh_terms: D000818:Animals; D005260:Female; D008297:Male; D010053:Ovary / Q000166:cytology* / Q000502:physiology; D011036:Poecilia / Q000033:anatomy & histology* / Q000502:physiology; D013094:Spermatozoa / Q000166:cytology* / Q000502:physiology; D052286:Viviparity, Nonmammalian
keywords: embryonic development; gynogenesis; intraovarian gestation; oogenesis; ovarian histology; parthenogenesis