Koya et al, 2000


Koya, Y. and Inoue, M. and Naruse, T and Sawaguchi, S. (2000) Dynamics of oocyte and embryonic development during ovarian cycle of the viviparous mosquitofish Gambusia affinis. Fisheries Science, pp. 63-70

Associated characteristics

Species Development state Trait Primary Data Secondary Data
Gambusia affinis Egg Oocyte diameter Mature oocytes were seen in follicles greater than 1.6 mm in diameter, and the number increased as the diameter became larger 1.6 mm
Gambusia affinis Egg Egg size after water-hardening Fertilised eggs began to appear in 1.8-1.9 mm follicles (2.4%) adn Increased to 16.0% in 1.90-2.0 mm follicles [The fertilized eggs were sligtly larger in diameter than mature oocytes] 1.85 mm
Gambusia affinis Egg Incubation time The ovarian events between two successive parturitions were summarized as follows: active vitellogenesis (days 0-3), maturation and fertilization (days 3-5), progress of embryonic developmentand beginning of vitellogenesis for the following gestation (day 10), and pre-parturition and progress of vitellogenesis (day 20). 1.5 days
Gambusia affinis Egg Temperature for incubation 25°C 25.0 °C
Gambusia affinis Egg Degree-days for incubation 100-120 [Seems to 5-6 days at 25°C] 110.0 °C * day
Gambusia affinis Female Maximum GSI value 20-22% , every 22 days during the reproductive season 21.0 percent
Gambusia affinis Spawning conditions Spawning temperature Mosquitofish need more than 18°C temperature and 12.5 h daylength for their reproduction, and that brood interval is kept almost constant if the water temperature and photoperiod are constant. 18.0 °C