Common Name: No Common Name

Scientific Name: Diplozoon Paradoxum

Kingdom: Animalia
Phylum: Plathelminthes

Class: Monogenea

Order: Polyopisthocotylea

Family: Diplozoidae

Genus: Diplozoon

Species: D. paradoxum

It is a common saying that two heads are better than one. But rarely do you find anyone who actually has two heads (with the exception of Siamese twins of course). The Diplozoon paradoxum literally has two bodies. These animals are actually quite unique and it is a wonder that they are not widely known. Yes, it is quite the extraordinary organism. The eggs of the Diplozoon paradoxum are laid in a fresh water fish’s gills. There it hatches into a larva stage. It will remain in that stage unless two larvae come together. Then the two larvae will undergo metamorphosis and become fused together. Reproduction isn’t really a problem because when two Diplozoon Paradoxums fuse together they are in a state of copulation. Therefore it can reproduce sexually. It size is usually around 0.7 millimeters which is approximately the size of a fingernail. Because it is a platyhemithe it has several hooks at its mouth which it will use to grab on to the gills of a fish. From there it will feed on the blood of a Cyprinid. Cyprinids are smaller fish that include the infamous goldfish. They (Diplozoon Paradoxum) have bilateral symmetry.


One thing is for certain, the Diplozoon paradoxum is not in danger. It virtually has no predators and it is only killed seldom by goldfish owners. Since it is a parasite, it rarely kills its host. So it doesn’t really endanger another species. The Diplozoon paradoxum really has a unique shape. Since it is two organisms, it is shapes almost like an ‘x’. It is not very commonly known because the best known animals belong to the phylum chordata. But it does play a role in society and is harmless to humans (which is probably why we don’t know so much about it). The only thing you want to watch out for is your goldfish!


Author: Mehtab B

Published: 02/2008

Sources: Stewart. "Detailed Taxonomy of the Parasitic Helminths ." Path. Online. 28 January 2008. "Monogeneans and Acanthocephalans." Aber. Online. 28 January 2008.

"Class Monogenea." Earth Life. Online. 28 January 2008.

"Diplozoon Paradoxum." Parasitology. Online. 28 January 2008.

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