ABSTRACT Present study was carried out to reveal the prevalent and unforeseen parasitic infection in commercially available ornamental fishes which may credit to their marketable value. Seven different species of ornamental fishes namely Carassius auratus (Gold Fish and Black Moor Gold), Cyprinus carpio (Koi Carp), Poecilia reticulate (Guppy), Rasbora daniconius (Slender Rasbora), Puntius conchonicus (Rosy Barbs), Trichogaster lasius (Brass gold) were screened for the occurrence of infection. Cyprinus carpio showed maximum infection caused by Argulus (Crustacean: Branchiuran) intensity=8-12 per fish. Argulus was observed as a primary infection which was followed by bacterial infection (dropsy) as secondary infection. While minimum infection was caused by Lernaea in Carassius auratus (intensity=1 per fish). Keywords – Argulus, ornamental fishes, parasitic, Lernaea REFERENCES Abd el-Mohsen, H.Mohamed and Amany M. (2013). 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