Microcotyle

These flukes are relatively large, about 5 mm in length, and live on the gills of marine and freshwater fishes. The prominent opisthaptor, at the right of the photo, has about two dozen pairs of small clamps. The presence of these multiple clamps easily places this fluke in the Polyopisthocotylea.

The prohaptor at the anterior (top of photo) is a simple structure, consisting of a small mouth (not visible) leading to a muscular pharynx with two lateral pouches. Posterior to the pharynx, the intestine splits into two ceca which proceed posteriorly and reunite near the opisthaptor. The ceca in this specimen are stained black, but are visible as thin bands just central to the thick, dark lateral bands of vitellaria.

The large oval mass in the centre of the body is actually a collection of numerous testes; the female reproductive structures are anterior to this but cannot be distinguished in this photo.