Pterophyllum is a small genus of freshwater fish from the family Cichlidae known to most aquarists as "Angelfish". All Pterophyllum species originate from the Amazon River, Orinoco River and Essequibo River basins in tropical South America. The three species of Pterophyllum are unusually shaped for cichlids being greatly laterally compressed, with round bodies and elongated triangular dorsal and anal fins. This body shape allows them to hide among roots and plants, often on a vertical surface. Naturally occurring angelfish are frequently striped longitudinally, colouration which provides additional camouflage. Angelfish are ambush predators and prey on small fish and macroinvertebrates. All Pterophyllum species form monogamous pairs. Eggs are generally laid on a submerged log or a flattened leaf. As is the case for other cichlids, brood care is highly developed.
The freshwater angelfish was first talked about by Lichtenstein in 1824. Being scientifically named Pterophyllum scalare (pronounced: Ter'-o-fill"um ska-la're), the meaning of Pterophyllum is "winged leaf".
It was not until the late 1920s to early 1930s that the angelfish was bred in captivity in the United States.
In 1963 another species of Pterophyllum were discovered, P. leopoldi, this species was described by Gosse. In the beginning they were first described under another name, with P. leopoldi becoming the valid scientific name. Prior to that a species by the name of Pterophyllum altum had been described in 1904 by J. Pellegrin. There may still be undiscovered species in the Amazon River and a recent detailed summary of the Pterophyllum genus has been proposed by H. Bleher consisting of 23 individual forms totalling a possible 12 still undescribed species is the most detailed analysis of the genus so far. New species of fish are discovered with increasing frequency, and, like P. scalare and leopoldi, the differences are extremely subtle. Scientific notations describe the P. leopoldi as having 29–35 scales in a lateral row and straight predorsal contour. Whereas, the P. scalare is described as having 35–45 scales in a lateral row and a notched predorsal contour. The leopoldi show the same coloration as scalare. Leopoldi can show a faint stripe between the eye stripe and the first complete body stripe and a third incomplete body stripe between the two main (complete) body stripes that extends three-fourths the length of the body. Whereas, the scalare's body does not show the stripe between the eye stipe and first complete body stripe at all, and the third stripe between the two main body stripes rarely extends downward more than a half inch, if even present. The leopoldi fry develop three to eight body stripes, with all but one to five fading away as they mature, whereas scalare only have two in true wild form throughout life.
Angelfish were bred in captivity for some 30 years prior to leopoldi being described; possibly longer outside the United States.
There are 11 different types of Angelfish.
P. altum Edit
Pterophyllum altum, also referred to as the Altum Angelfish, Deep Angelfish, or Orinoco Angelfish, occurs strictly in the Orinoco River Basin and the Upper Rio Negro watershed in Southern Venezuela, Southeastern Colombia and extreme Northern Brazil. The species is the largest and rarest of the genus and specimens exceeding 50 cm in height (from tip of dorsal to tip of anal fin) have been reported in the wild; in aquariums, specimens are known to have grown to over 40 cm. Its natural base color is silver but with three brownish/red vertical stripes and red striations into the fins. The species may show red spotting and a blueish green dorsal overcast when mature and when aroused exhibits a black operculum spot. Characteristic of this species is an acute incision or notch above the nares (supraorbital indention). All true Orinoco Altum specimens show this trait, whereas commercial hybrids product of crosses to Pterophyllum scalare, that are occasionally performed by breeders to sell them as "Orinoco Altum", may not exhibit the trait or it may appear in a lesser degree. The true wildcaught Orinoco Altum is among the most challenging among tropical fish to breed in captivity. Most Altum Angels are more frequently found in the well oxygenated, extremely soft waters of Upper and Middle Orinoco tributaries shed from the Guiana Shield Highlands, preferring a pH range between 4.5 to 5.8. These are very transparent blackwaters with almost nil conductivity. Temperature range in these waters is between 78 and 84 °F (26 and 29 °C). They are also found in the Atabapo River and Inirida River floodplain, down the Casiquiare and Guainía floodplain where the Rio Negro is born, before entering Brazilian territory. Unlike P. scalare (mentioned above) which prefer to spawn on the submerged leaves of plants and trees in the flooded rainforest, P. altum prefers to spawn on submerged roots and tree branches in a moderate water current. This species is recommended for intermediate to advanced aquarists due to the detailed maintenance it requires for proper health. Pterophyllum altum is the national fish of Venezuela and an image of the fish appears on some currency bills of that country.
P. leopoldi Edit
Pterophyllum leopoldi, also referred to as the teardrop angelfish, leopold's angelfish, dwarf angelfish, or Roman-nosed angelfish, is a river dwelling angelfish species that originates from rivers in the Amazon River basin along the Solimões River, Amazon River, and Rupununi River. It is distinguished from other members of the Pterophyllum genus by the absence of a pre-dorsal notch and by the presence of a black blotch at the dorsal insertion on the 4th vertical bar. The species was originally described as Plataxoides leopoldi in 1963 by J.P. Gosse, and is frequently misidentified as P. dumerilii when the species is imported in the aquarium trade. P. leopoldi is the smallest of the angelfish species and the most aggressive.
P. scalare Edit
Pterophyllum scalare, the species most commonly referred to as angelfish or freshwater angelfish, is the most common species of Pterophyllum held in captivity. Its natural habitat Amazon River basin in Peru, Colombia, and Brazil, particularly the Ucayali, Solimões and Amazon rivers, as well as the rivers of Amapá in Brazil, the Oyapock River in French Guiana and the Essequibo River in Guyana. It is found in swamps or flooded grounds where vegetation is dense and the water is either clear or silty. Its native water conditions range from a pH of 6.0 to 8.0, a water hardness range of 5 - 13 dH, and water temperature ranging from 24 to 30 °C (75 to 86 °F). It was originally described as Zeus scalaris in 1823, and has also been described be several different names, including Platax scalaris, Plataxoides dumerilii, Pterophillum eimekei, Pterophyllum dumerilii, and Pterophyllum eimekei.
Angelfish in the fishkeeping hobbyEdit
Angelfish are one of the most commonly kept freshwater aquarium fish, as well as the most commonly kept cichlid. They are prized for their unique shape, color and behavior.
The most commonly kept species in the aquarium is Pterophyllum scalare. Most of the individuals the aquarium trade are captive-bred. Sometimes, Pterophyllum altum is available. Captive bred P. altum is available but occasionally. Pterophyllum leopoldi is the hardest to find in the trade.
Angelfish are kept in a warm aquarium, ideally around 80 °F (27 °C). They will do best if fed a mixture of flake, frozen and live food. Care should be taken to not overfeed, they will continue to eat even what they do not need to. This will lead to a buildup of fats resulting in inactivity and early death. Angelfish will do best if kept in an acidic environment, pH should be below 7.5 (note: 7.5 is still slightly alkaline – acidic is defined as below 7.0). All angelfish will prefer water with a pH of at most 7.0. Though most Pterophyllum scalare will thrive in a wide range of pH values. Even though angelfish are a member of the Cichlid family they are generally peaceful, however; the general rule "big fish eat little fish" applies. Small fish such as the Cardinal Tetra will be eaten, as they can be picked off during the night. Aggressive fish should not be kept with angelfish because their flowing fins are vulnerable to fin nipping. Some smaller more aggressive fish may even nip at the fins of these fish. Angelfish also enjoy backwater aquariums with plentiful wood and dark places to relax.
P. scalare is relatively easy to breed in the aquarium, although one of the results of generations of inbreeding is that many breeds have almost completely lost their rearing instincts resulting in the tendency of the parents to eat their young. In addition, it is very difficult to accurately identify the gender of any individual until they are nearly ready to breed.
Angelfish pairs form long-term relationships where each individual will protect the other from threats and potential suitors. Upon the death or removal of one of the mated pair, breeders have experienced both the total refusal of the remaining mate to pair up with any other angelfish and successful breeding with subsequent mates.
Depending upon aquarium conditions, P. scalare reaches sexual maturity at the age of six to twelve months or more. In situations where the eggs are removed from the aquarium immediately after spawning, the pair is capable of spawning every seven to ten days. Around the age of approximately three years, spawning frequency will decrease and eventually cease.
When the pair is ready to spawn, they will choose an appropriate medium upon which to lay the eggs and spend one to two days picking off detritus and algae from the surface. This medium may be a broad-leaf plant in the aquarium, a flat surface such as a piece of slate placed vertically in the aquarium, a length of pipe, or even the glass sides of the aquarium. The female will deposit a line of eggs on the spawning substrate, followed by the male who will fertilize the eggs. This process will repeat itself until there are a total of 100 to more than 1,200 eggs, depending on the size and health of the female fish. As both parents care for the offspring throughout development, the pair will take turns maintaining a high rate of water circulation around the eggs by swimming very close to the eggs and fanning the eggs with their pectoral fins. In a few days, the eggs hatch and the fry remain attached to the spawning substrate. During this period, the fry will not eat and will survive by consuming the remains of their yolk sacs. At one week, the fry will detach and become free-swimming. Successful parents will keep close watch on the eggs until they become free-swimming. At the free-swimming stage, the fry can be fed newly-hatched brine shrimp (Artemia spp.) or microworms. It is generally accepted that brine shrimp are the superior choice for fast growth rates of fry.
P. altum is notably difficult to breed in an aquarium environment.