Microcotyle polymixiae facts for kids

Microcotyle polymixiae is a tiny worm that lives on the gills of fish. It's a type of monogenean, which means it's a parasite. Parasites are creatures that live on or inside another animal (called a host) and get their food from it. This worm belongs to a family called Microcotylidae.

Scientists first found and described Microcotyle polymixiae in 1968. They studied 82 samples of these worms. They found them living on the gills of a fish called the silver eye, Polymixia japonica, near Hawaii.

What Does It Look Like?

Microcotyle polymixiae looks like other worms in its group, Microcotyle. It has a flat body, shaped a bit like a spear. It's narrow at the front and gets wider. These worms are usually between 3.5 and 8.5 millimeters long. That's less than half an inch!

The worm's body has two main parts:

• The front part holds most of its organs.
• The back part is called the haptor. This haptor is shaped like a small axe. It has 57 to 88 special gripping tools called clamps. These clamps are arranged in two rows, one on each side of the haptor. The clamps help the worm hold on tightly to the fish's gill.

At the very front of the worm, it has two small, strong suckers. These suckers are muscular and help the worm attach itself. They don't have any hooks or teeth.

How It Eats

The worm has a mouth at its front end. Food goes from the mouth into a simple tube called an esophagus. Then it goes into a muscular, round part called a pharynx. After that, the food moves into the intestine. The intestine has two branches that go along the sides of the worm's body. These branches end separately at the back of the worm.

Where It Lives

The main fish that Microcotyle polymixiae lives on is the Silver eye, also known as Polymixia japonica. This fish is a type of Polymixiidae.

Scientists first found this worm off the coast of Hawaii. So far, it seems this is the only place where this specific parasite has been mentioned in scientific papers.

Other types of Microcotyle worms have also been found in Hawaii. For example, Microcotyle bothi and Microcotyle emmelichthyops were found on different kinds of fish in the same area.