The bluespine unicornfish must be a contender for any ‘Grumpiest Looking Fish’ awards. This one though was enjoying the attention of a small yellow and blue Hawaiian cleaner wrasse.
Cleaner wrasses establish territories where other fish come to be cleaned, removing mucus, dead tissue, and parasites from their customers. This service is obviously valued by other fish. They will line up to be cleaned, waiting their turn. Often times, their expressions are quite blissful during the process. But most significant, cleaner wrasse perform their services on bigger fish, including predators, without becoming prey.