|Masked Butterflyfish (Chaetodon semilarvatus) in the Red Sea|
by B. N. Sullivan
The Masked Butterflyfish (Chaetodon semilarvatus) is one of just a few species in the family Chaetodontidae that mates for the long term, thus they are most often seen in pairs. They live in the Red Sea and the Gulf of Aden.
These are brilliantly colored fishes with bright yellow, vertically lined bodies. They have a distinctive grayish blue eye mask, the feature for which they are named. "Semilarvatus" in Latin means "Half-mask." The species has several other common names, including the Blue-cheek Butterflyfish and the Golden Butterflyfish.
I photographed this pair against a backdrop of colorful Nephtheid soft corals in the Red Sea. Each fish was approximately 18 cm (7 in) long.