Also called: Chinese Trumpetfish
Scientific name: Aulostomus chinensis
Trumpetfish belong to the same family as seahorses and cornetfish. They are carniverous, and tend to hover over the reef while slowly sneaking up on their prey, which consists mostly of small wrasses and other tiny reef fish.
It's easy to miss these fish, as they're so thin and move slowly. This one stood out only because he was moving against the brightly colored coral.
Also called: giant kingfish, lowly trevally, barrier trevally, ulua.
Scientific name: Caranx ignobilis
The giant trevally are the kings of the reef, the apex predator. If you're swimming along and all the little fish suddenly dart into the coral for protection, look around and you'll probably see one of these guys on the hunt.
Scientific name: Aeoliscus strigatus
Razorfish get my vote as one of the stranger fish species. They always swim in schools, in a vertical orientation with their heads pointing towards the bottom. As if that wasn't strange enough, they seem to swim with amazing synchronisity, making rapid direction shifts suddenly and all together.
Scientific family: Caesionidae
Fusiliers are sleek fish related to snappers. They form large schools that are constantly on the move. Often you may find mixed schools of fusiliers containing more than one species.
Identifying fusiliers - generally - is relatively easy. They're sleek, and most species have "V" shaped tails, often with black tips. Figuring out exactly which species you've found can be harder, as they're not well documented.
Scientific name: Zanclus cornutus
Moorish idols are a singular species, although they can be easily confused with bannerfish. You'll find them singly or in pairs throughout Southeast Asia. The long snout with a small yellow or orange saddle is their distinctive feature.
Scientific name: Heteroconger hassi
Parrotfish are distant relatives of Wrasses. The main difference is that in Parrotfish, the teeth have been fused together to form a sort of 'beak'. This, together with their often colorful appearance, is why the're called Parrotfish. The hard beak is used to scrape algae off rocks and bite into hard corals as well. The rock and coral is ground up and passes through the fish's digestive system, contributing a major portion of the sand and sediment to reefs.
Another thing that Parrotfish have in common with birds is that females are generally less coloful than the males. Unlike birds, but in common with many reef fish, the Parrotfish goes through a female to male transformation at some point in their life.