Aracha

The Aracha are small, one-eyed infantile Moldarachs found in the Lanayru Mining Facility in Skyward Sword. Aracha who have lived for a millenium grow into Moldarachs. They are arguably the easiest enemy in the game, as they take one sword slash to defeat, and they do less damage than a Keese.

Characteristics
Aracha are found on floors of caves and dungeons, in piles of dust or sand, and clinging to climbable walls much like the Skullwalltula. They will leap at Link, or crawl onto him if he encounters them on a wall, and attack while clinging to him until they are thrown off. They can be easily killed with a swipe of the sword or with any projectile, including Slingshot pellets. One gust of the Gust Bellows will knock them over and away from Link, although they right themselves quickly.

Being physically weak, they only make a real threat of any kind to Link when they appear in large numbers, upon which point they can swarm and surround him, latching on and attacking as a group. It is still unlikely that they will cause much danger even in these situations, however.

Trivia

 * These creatures greatly resemble the Aruroda from The Adventure of Link in that they're both one-eyed scorpions.
 * Aracha are also similar to Baby Gohma from Twilight Princess in that they are small, incredibly weak offspring of the dungeon's boss that are only a danger in large groups.