2010 Volume 45 Issue 4 Pages 175-178
Heterobothrium ecuadori is a gill monogenean infecting the gills of the bullseye puffer fish Sphoeroides annulatus and feeding fish blood. This experimental study was performed to describe the juvenile stages of H. ecuadori and to determine the time required to reach the adult stage at 20-23°C. Uninfected bullseye puffer fish were exposed to oncomiracidia and sampled at intervals to obtain worms of different developmental stages. Between 5 and 10 days after the exposure, the first and second pairs of clamps were observed in worms along with the emergence of the third clamp. Four pairs of clamps were observed on day 15, and primordial male copulatory organ, testes and ovary were found on day 20. Adult parasites started to appear between 25 and 30 days post-infection. The time required for egg laying was estimated to be 33 days, based on the first collection of eggs in the rearing water.