Blacknosed Barberfish Butterflyfish - NicaraguaJohnrandallia nigrirostris Johnrandallia nigrostris is a species of marine fish that belongs to the family of Chaetodontidae and is found in the East Pacific, specifically around the Sea of Cortez & the Islands of the Galpagos. Acts as a cleaner fish in tanks as well as the wild. Commonly housed in home aquariums with other butterflies. Be sure to house in aquariums with plenty of swimming space and liverock for grazing.