The angelfish is a favorite New World cichlid among tropical fish aquarists. Three angelfish species have been catalogued. Pterophyllum scalare is the most common angelfish kept as a pet; the others are P. altum and P. leopoldi. The common angelfish has been bred to produce hundreds of phenotypes that display different colors, patterns and fin shapes.
Common angelfish originate in South America, in the Amazon basin within the countries of Peru and Brazil. Freshwater angelfish have diamond-shaped body with long, thin dorsal and ventral fins, and short, forked tail fins. Wild P. scalare are silver with four vertical black stripes and red eyes. They average 5 inches in length. The most common pet angelfish have this same appearance. The stripes help the angelfish camouflage themselves among the reeds and weeds in their natural environment. Angelfish are reasonably tolerant of other fish, unlike many cichlid species that are extremely territorial and aggressive.
The tall angelfish is the common name for Pterophyllum altum. This fish is about 5 inches long and 8 inches tall including its fins. P. altum's profile is also steeper than that of P. scalare. The altum angel has reddish brown stripes instead of the typical black stripes of P. scalare. Fish referred to as Peruvian altums are actually very tall P. scalare. The tall angel lives in deeper water than other angel species; in the wild or in very large aquariums may reach 18 to 20 inches in height. In nature, it lives in the Orinoco River near the Colombia-Venezuela border.
Called the teardrop angelfish, Leopold's angelfish, the dwarf angelfish or the Roman-nosed angelfish, P. leopoldi is the most recently discovered species within the genus. It originates from the middle Amazon River and the upper Essequibo drainage area. The Leopoldi angelfish has paler stripes than the other two Pterophyllum species. They're called dwarf angelfish because they reach a maximum length of 4 inches long. Unlike P. scalare and P. altum, the teardrop angel has no predorsal notch. A black spot below the dorsal fin is another quick way to distinguish the dwarf angelfish from other Pterophyllum species. Leopold's angelfish is the least common species kept in aquariums and is rarely bred in captivity.
Phenotypes are divisions made within a species based on the representation of certain genetic traits. Through selective breeding, aquarists have developed hundreds of P. scalare phenotypes. Some are common and others are rare and difficult to breed. For instance, pearlscale angelfish are among the rarest angelfish varieties. These fish have rippled, shimmering scales, and are sometimes called diamond angelfish. Golden angelfish, or butterballs, are yellow to orange in color and have no stripes. Several black angelfish phenotypes may have brassy or matte scales along with fin variations. Marbled angelfish have mottled color patterns, often in silver, black or gold. Koi angelfish have spots of orange and black on white backgrounds. Very few phenotypes exist for P. altum, and none are known in the hobby for P. leopoldi.
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