The fishery of bony fishes has an economic important in southern part of Caspian Sea ,but there are few reports about the pathogens of them in this area .Eustrongylides excisus , a parasite (Nematoda: Dioctophymidae) can damage the muscles of bony fishes . So, consumers avoid to buy the infected fish. Hence , the parasite can cause economic loss.In order to determine the occurance and intensity...

Scanning Electron Microscopy was used to describe the eggs of Georgecraigius fluviatilis (Lutz). Length is 722.8±39.6 µm and width is 177.1±9.8 µm. Diameter of the micropylar disk, surrounded by an irregular flattened collar, is 28 µm. The outer chorionic sculpture consists of cells of irregular shapes, containing tubercles with pitted surface. In the ventral region, tubercles of several diamet...

This first comprehensive study of the peripheral olfactory organ from a representative of the large and economically important order of teleost fishes, the Perciformes, shows a compact structure with olfactory sensory neurons distributed widely throughout the olfactory chamber. The spatial organization of the nasal cavity in the bottom-dwelling round goby (Gobiidae, Neogobius melanostomus) was ...