Family-Animalia: Pomacanthidae

Marine angelfish are perciform fish of the family Pomacanthidae. They are found on shallow reefs in the tropical Atlantic, Indian, and mostly western Pacific Oceans. The family contains seven genera and about 86 species. They should not be confused with the freshwater angelfish, tropical cichlids of the Amazon Basin.

Description

With their bright colours and deep, laterally compressed bodies, marine angelfishes are some of the more conspicuous residents of the reef. They most closely resemble the butterflyfishes, a related family of similarly showy reef fish. Marine angelfish are distinguished from butterflyfish by the presence of strong preopercle spines (part of the gill covers) in the former. This feature also explains the family name Pomacanthidae; from the Greek πομα, poma meaning "cover" and ακάνθα, akantha meaning "thorn".

Many species of marine angelfishes have streamer-like extensions of the soft dorsal and anal fins. The fish have small mouths, relatively large pectoral fins, and rounded to lunate tail fins. The largest species, the gray angelfish, Pomacanthus arcuatus, may reach a length of 60 cm (24 in); at the other extreme, members of the genus Centropyge do not exceed 15 cm (5.9 in). A length of 20 to 30 cm (7.9 to 11.8 in) is typical for the rest of the family. The smaller species are popular amongst aquarists, whereas the largest species are occasionally sought as a food fish; however, ciguatera poisoning has been reported as a result of eating marine angelfish.

Angelfish vary in color and are very hardy fish. They can easily adapt to pH and hardness changes in water and can handle conditions that are not considered to be perfect. They are usually a long-living species and are easy to care for. They were very expensive in the aquarium trade when first discovered, but have become more popular and therefore less pricey.

The queen angelfish grows to be 45 cm (18 in). With neon blue and yellow scales and iridescent purple and orange markings, surprisingly it is not conspicuous, and actually hides very well, and is very shy.

As juveniles, some species are different colors than when they reach adulthood. For example, the Blue Angelfish is a vibrant, electric blue color with black and white stripes or spots. When they reach adulthood, they turn a grayish color with yellow and blue fins and dark spots on their bodies.

Reference: Wikipedia