moorish idol

The Moorish idol (Zanclus cornutus) is a marine fish species that resembles butterflyfish and angelfish. The Moorish idol differs from butterflyfish in having a black triangular tail fin.

They have distinctively compressed and disk-like bodies, and stand out with contrasting bands of black, white and yellow. The fish have relatively small fins, except for the dorsal fin, whose six or seven spines are dramatically elongated to form a trailing, sickle-shaped crest.

This tag implicates fish (learn more).