Squiggler

From the Super Mario Wiki

A Squiggler is a miniature Wiggler that appears in New Super Mario Bros.

With three body segments and a head about twice the size as the other segments with a sprout on it's head, this tiny Wiggler crawls around the perimeter of pipes. Squigglers are only seen in World 7-A and are obviously the baby versions of the Wigglers. It can be inferred that they are born in pipes. When they mature enough they (presumably) become a Wiggler, then a Flutter.

They also reappeared at Mario & Luigi: Bowser's Inside Story, this time with a more vivid color.

New Super Mario Bros.
Protagonists	Mario • Luigi • Princess Peach • Toadsworth
Worlds	World 1 • World 2 • World 3 • World 4 • World 5 • World 6 • World 7 • World 8
Bosses	Bowser Jr. • Bowser • Mummipokey • Cheepskipper • Mega Goomba • Petey Piranha • Monty Tank • Lakithunder • Dry Bowser
Items	Super Mushroom • 1-Up Mushroom • Mini Mushroom • Mega Mushroom • Fire Flower • Blue Shell • Star • Coin • Silver Coin • Red Coin • Red Ring • Big Star
Enemies	Amp • Balloon Boo • Banzai Bill • Blockhopper • Bob-omb • Boomerang Bro. • Boo • Broozer • Bullet Bill • Buzzy Beetle • Chain Chomp • Cheep-Cheep • Cheep-Chomp • Deep-Cheep • Dry Bones • Fire Bro. • Fire Chomp • Fire Snake • Goomba • Hammer Bro. • Kab-omb • Koopa Paratroopa • Koopa Troopa • Lakitu • Mega Cheep-Cheep • Mega Deep-Cheep • Mega Unagi • Micro-Goomba • Moneybag • Paragoomba • Piranha Plant • Podoboo • Pokey • Scuttle Bug • Skeeter • Snailicorn • Snow Spike • Spiny • Splunkin • Squiggler • Super-Whomp • Super Dry Bones • Super Piranha Plant • Super Thwomp • Sushi • Sumo Bro. • Swooper • Thwomp • Unagi • Venus Fire Trap • Wiggler • Whomp