Cosmic Scuttle Bug

From the Super Mario Wiki

A large swarm of Cosmic Scuttle Bugs.

Cosmic Scuttle Bugs are a possible relative of normal Scuttle Bugs that appear only in Super Mario Galaxy. Cosmic scuttle bugs are striped and, unlike their bright yellow cousins, mostly dark and dull in color. They can be either brown and gray or blue and purple. Some will hang from ceilings and overhangs by a thread of webbing. They appear mostly in the Space Junk Galaxy and Ghostly Galaxy, and make appearances in other galaxies and Bowser Jr.'s Airship Armada.

The grounded Cosmic Scuttle Bugs will only attack by jumping into the air and floating there for several seconds before falling back to the ground in hopes of landing on Mario. The kind that hang from ceilings will swing back and forth on their threads like a pendulum in an attempt to damage the player. Both can be stunned by the Star Spin and defeated by either kicking the stunned enemy or by a single stomp.

They are found in large numbers along the path leading to Tarantox, this may signify that they are related.