Angelfish

Scientific name: Pomacanthus paru

Also called: Yellowface Angelfish

Scientific name: Pomacanthus xanthometopon

Yellowmasks are relatively common on the reefs throughout Southeast Asia. I've seen them around Koh Tao and the Similans in Thailand, as well as Malaysian and Indonesian reefs.

Also called: Royal Angelfish

Scientific name: Pygoplites diacanthus

Regal Angefish can be found in offshore reefs throughout Southeast Asia. Like most Angelfish, they rely on boulders, caves and coral crevices for shelter, which is why it's so hard to get a good picture of them.

Scientific name: Pomacanthus imperator

The Emperor Angelfish can easily be mistaken for other Angelfishes. The distinguishing features are the black mask around the eyes and the horizontal stripes.

Scientific name: Pomacanthus annularis

The Blue-Ringed Angelfish is one of the most striking fish on the reef. In low light, the blue strips seem to fluoresce. It's also one of the most difficult fish to photograph, constantly changing directions whenever you want to take a picture.