This small crustacean anchored to buildings by feeder roots through which it absorbed nutrients. It retracted into its shell when threatened. The shadow barnacle reproduced by releasing "egg seeds" and "sperm pollens" into the air.
It consisted of a tubular mouth, a shelled pod, and retractable anchor tendrils. It could also move by using its claw-legs, and it had external filaments that could be withdrawn into its mouth.
They were able to survive the vongforming of Coruscant.