The present studywas carried out to survey ectoparasites fauna of gold fish (Carassius auratus) in Mazandaran province (Iran) from April 2009 to March 2010. A total of 200 samples were obtained from 10 ornamental fish supply centers and transferred alive to the laboratory. In this study, the following ectoparasites were isolated: Ichthyophthirius multifillis , Trichodina spp., Gyrodactylus spp., Dactylogyrus vastator, Dactylogyrus baueri and Argulus coregoni. The results revealedthat 28.5% of sampled goldfish were infested with ectoparasites .The frequency of protozoan infestations were 15% (9%I. multifillis and 6% Trichodina spp.), the frequency of monogenean ectoparasite was 12.5% (5% Gyrodactylus spp., 5% D. vastator and 2.5% D. baueri) and that of crustaceans (A. coregoni) was 1%. The most frequently reported infestation was due to I. multifillis causative agent of white spot disease.Enhancing the health management through improving water quality and bio-security is the most effective way to prevent the parasite infestations.

Pick handle barracuda (Sphyraena jello) ) is one of the most important commercial species in the Persian Gulf. In order to investigate prevalence and intensity of nematoda, 150 S. jello  from three sites (Khuzestan, Bushehr and Hormozgan provinces) of the Iranian coast of the Persian Gulf were monthly investigated in the period 2012-2013. The nematodes belonging to the genus Hysterothylacium (family Raphidascarididae) were isolated from the abdominal cavity and digestive tract with a prevalence of 12% and mean intensity of 4.8. Intensity of infestation was increased with size of the host (P<0.05). This study is the FIrst report of presence of the third and fourth- stage of an unreported type of the third and fourth- stage of an unreported type of Hysterothylacium  larvae in S. jello  from the Persian Gulf.