Common Name: Gyrodactylus elegans
Scientific Name: Gyrodactylus elegans
Species: G. elegans
Gyrodactylus elegans is one of the best-known species of the Monogenea flatworms. It is most famous for its peculiar method of reproduction. G. elegans is a gill and skin parasite of the European carp. It grows to only 1mm long.
It can infest a carp very rapidly owing to it method of reproduction. G. elegans reproduces in a most unique way; several offspring develop from a single egg. The egg releases one offspring at a time and the living parasite carries the others taking on the parent role. Since all the flatworms come from the same egg they are like sisters. However, since one is born and cares for the next one to emerge it is considered the parent of the following generations. It is very much like the old Russian doll where you open one and get a small one, then when you open that one there is yet another.
G. elegans gives live birth to one worm per generation. The new worm infects the same fish as the parent, so in a short amount of time, a fish can be infested with large colonies of parasites. There have been studies that show in cold water the parasites are limited to the gills of carp (goldfish), in warm, they also invade the fins.
Author: Merrick S
Photo Credit: These images are a work of the Centers for Disease Control and Prevention, part of the United States Department of Health and Human Services. As a work of the U.S. federal government, the image is in the public domain.
Diagram by: Adrienne L