Black Spiked Crab w/ Purple Markings

There are 3 tameable creatures with this look.

Black Spiked Crab w/ Purple Markings
Can Be Tamed
Path of Suffering, Broken Shore
Present when world quest, "Mud Mucking" active. Randomly spawns when clicking on Disturbed Mud.
Can Be Tamed
30-35Abyssal Depths
Found at the bottom of Coldlight Chasm.
Can Be Tamed
50Gorgonian Outlook, Nazjatar
These crabs may be phased. If so, they can still be viewed and pulled out of the area for taming from the adjacent area to the west: The Empress's Approach.
* Level scaling: In Shadowlands 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.