Argulus japonicus Thiele, 1900 
Argulus japonicus Dorsal View

Argulus japonicus Ventral ViewThe genus Argulus (Crustacea: Branchiura) has a worldwide distribution. It is an ectoparasite, primarily found on fish. The classification is as follows:
Phylum Arthropoda
Subphylum Crustacea
Class Maxillopoda
Subclass Branchiura
Order Arguloida
Family Argulidae
Genus Argulus
The photos above were taken by Mr. Kevin Charton of Delta Optical with TAMU-T's new dissecting microscope and digital camera. Specimens supplied by Tim Eddings.
Some links for Argulus