A single parasite (Cyclochaeta) enlarged 150 diameters

A single parasite (Cyclochaeta) enlarged 150 diameters. The “mouth” may be seen entering one side of the parasite as well as the gear shaped “skeleton”. Cyclochaeta is a complex single-celled parasite living on the skin and gills of fish and causing a severe irritation. Epidemics among small fish are frequently caused by this parasite.

Photo Location: Washington, Seattle