No. 98: Mar-Apr 1995
A tiny, transparent, still-nameless fish swimming in the Araguaia River in the Amazon Basin comes out at night to suck blood from its victims. It wriggles into the orifices of animals, anchors itself with two hook-shaped teeth, and gorges on blood. The gills of other fish are its usual targets, but the orifices of other animals, including humans, are fair game, too.
This Amazonian fish is only about 1 centimeter (less than ½ inch) long, making it smaller than the infamous candirus that threaten bathers in other South American streams. Once a candiru slithered into a cut on a researcher and could be seen wriggling under the skin toward a vein. Candirus also anchor themselves inside their victims' orifices, requiring surgical removal.
(Homewood, Brian; "Vampire Fish Show Their Teeth," New Scientist, p. 7, December 3, 1994.)
For more on this fish, see BHX12 in our catalog: Biological Anomalies: Humans III. To order: go to here.