About Cyerce nigricans (Pease, 1866)
Cyerce nigricans (Pease, 1866) is a species of sacoglossan sea slug, a shell-less marine opisthobranch gastropod mollusk that belongs to the family Caliphyllidae. Like other sea slug species, it lives on reef flats and similar habitats. Unlike other members of the genus Cyerce, Cyerce nigricans does not have cryptic coloration. It is commonly a well-known representative species of the Great Barrier Reef due to its striking coloration, which typically includes combinations of black, yellow, red, and orange. The shape and color of this species' cerata are often compared to the wings of a butterfly. This sea slug has evolved autotomy, meaning it can drop portions of its cerata when it feels threatened. This species has been recorded in the western and central Pacific Ocean, as well as the Indian Ocean. The most recently documented sighting of the Black-and-gold Sapsucking Slug, the common name of this species, was in the Pemba North Region on January 4, 2026.
