Reproduction and Development of the Dark-sided Frog Hylarana nigrovittata Sensu Lato at the Cologne Zoo

Abstract. We report on the keeping and breeding of the dark-sided frog at the amphibian breeding unit of the Cologne Zoo Aquarium. Hylarana nigrovittata sensu lato represents a species complex, with the current research referring to a population from northern Thailand. Oviposition in captivity commenced in accordance with the natural habitat’s dry season, but continued year-round at Cologne Zoo. The crucial factor, which was introduced in order to increase reproduction in captivity, was an increase in misting, in combination with raised water levels. Oviposition also occurred under drier conditions, but to a lesser extent. Development depends on water temperature and generally takes at least 2.0–2.5 months to metamorphosis, at water temperatures of 22–26°C. We provide here for the first time an overview of characteristic developmental stages for the dark-sided frog complex.