Blood Sucking Lamprey.

 The Lamprey, which is also sometimes called a lamprey eel is a fish of sorts, which is jawless and has a toothed funnel for a mouth that is built for sucking.
Truly the Dracula of the deep, lampreys are well known for the fact that they attach to the flesh of other fish and suck their blood.

In zoo circles, the lamprey is not a true fish since it is very different in makeup and in physiology.

Lampreys are most often found in either coastal or in fresh water. They do resemble the eel in that they don’t have scales, and are in fact very long in body size.
The adult lamprey can be as long as nearly four feet.
They have no fins, big eyes, and one nostril on the top of their head, and seven gills on either side of the long body.
A unique feature of the lamprey is that it has no bone, but a totally cartilage body skeleton.
The lamprey has a good defense system to combat iron overload and have other natural defenses that are related to their diet.

The Lamprey starts out as a burrowing larvae, completely toothless, with only very basic eyes and will feed completely in microorganisms. This stage of lamprey life can last as long as five to seven years.
When they become adults it is nearly as unique as the caterpillar becoming a butterfly.
They tranform in myriad ways, involving internal organ restructuring, gaining eyes and turning from a filter of sorts into a blood eater.

Adult lamprey‘s will feed by attaching themselves to a fish, and will then secrete a powerful anticoagulant that may last for weeks or months.
They will fall off the host fish when they are either full and satisfied or the host fish dies.

When they reproduce, the lamprey will always return to the fresh water, and will spawn much as the salmon does. The lamprey will lay eggs, while the males excrete sperm and end their lives.