Do cleaner wrasses rub on reef manta rays to remove their own parasites?
Cleaner wrasses of the genus Labroides are the epitome of a cleaner fish. Herein we describe two cleaner wrasse
species, Labroides bicolor and Labroides dimidiatus, displaying a behaviour known as chafing or flashing. When chafing, a fish rubs itself against sandy bottoms, rocks, vessels, or other rough surfaces including sea turtles and sharks. We recorded the two cleaner wrasse species rubbing themselves against the rough skin of reef manta rays, Manta alfredi, on a coral reef cleaning station at Yap, Micronesia, western Pacific. As chafing is a way to relieve skin irritationand an alternative to reduce external parasites, we suggest that these specialised wrasse species use this behaviour to remove their own ectoparasites when other cleaning services are unavailable. The recorded ray-wrasse cleaning association is noteworthy, since the rays provide food and cleaning opportunity to the wrasses at the same time..