Magenta Worm

There are 2 tameable creatures with this look.

Magenta Worm
Exotic family: Beast Masters only - level 10+.Exotic Family
Can only be used by Beast Mastery hunters that have reached level 10.
Can Be Tamed
10-30(NPC Level:

Hillsbrad Foothills
Retains its original name after taming.
Can be found swimming in the pond south of Tarren Mill.
Can Be Tamed
Level scaling: Most NPCs will scale with the Hunter's level, within the constraints of their level range. Hunters can tame regular NPCs up to 2 levels higher than them, but can only tame elite NPCs of the hunter's level or below.