Silverfish

The Silverfish is a new mob that is planned for Beta 1.8. Its texture can currently be found in the Beta 1.7.3 minecraft.jar. Silverfish will pop out of stone bricks that the players mine, and then attack them. Silverfish will also spawn near others of their kind, which can cause a swarm if not controlled. They scurry away after the player moves a short distance.

History
The image, silverfish.png, was added to the mobs folder in the Beta 1.7 update. The silverfish mob was later announced for 1.8.

In the Beta 1.8 update leak, Silverfish can be found in stone bricks in Strongholds

Trivia

 * In real life, silverfish are small, wingless insects that are often found in dark areas in buildings. They are infamous for damaging wood and paper-based products.
 * Jeb confirmed that the silverfish won't be a water mob, ruling out the possibility of the Silverfish being an actual fish.


 * It is also believed that they are the "scary mob" referred to by 242_girl being added in 1.8. Though some believe that Endermen are the "scary mob", it is impossible since the Endermen were made by Notch, whereas Jeb made the "scary mob" some time earlier.