Crab

Crabs are decapod crustaceans of the infraorder Brachyura, which are generally covered with a thick exoskeleton and come armed with a pair of pincers. They are delicious. In the Crash universe, they also make a few appearances as generic enemies.

Crash Bandicoot
Crabs are the first enemies encountered in this game - and, by extension, the entire series. They appear mainly on N. Sanity Beach. They do not directly attack Crash, instead simply walking from side to side while blindly snapping their pincers. They easily fall to a jump or spin attack.

Crash Bandicoot 2: Cortex Strikes Back
A crab makes a cameo appearance in the less-than-100% completion ending, passing by as Coco wonders what happened to Doctor Neo Cortex and his Cortex Vortex.

Crash Bandicoot: The Wrath of Cortex
crabs scuttle from side to side in level Crash And Burn in an attempt to stop Crash. They can be defeated by spinning.

Crash Twinsanity
Crabs reappear as generic enemies. They appear on N. Sanity Beach and Jungle Bungle - unusual, as real-world crabs typically do not live in jungles. Their appearance seems to be a deliberate throwback to the first game in the series. However, these crabs wear shells, implying that they are hermit crabs and, therefore, not the same crabs that Crash Bandicoot killed in Crash Bandicoot.In this game they can dig underground.

Trivia

 * The appearance of crabs as enemies in the Crash games appears to be a reference to the many famous crab enemies from Nintendo's rival Mario series, including Sidesteppers from Mario Bros. and Clawglip from the true Super Mario Bros. 2.