This is a well-known genus of graceful cichlids from various tributaries, drainages and swamps of the Amazon, Orinocco and Guiana Shield river systems in South America. Their laterally-compressed bodies facilitate movement among the grasses of the llanos and the root, branch and vegitations-laden areas typical of much of flooded rainforests, and their vertical stripes aid in camouflage. To date, three distinct species have been identified:
Altum Angelfish, Orinoco Angelfish
Pellegrin, 1903 Distribution:
Distribution: Endemic to the Orinoco River
Leopolds, Dwarf, Teardrop, Angelfish, Roman-nosed Angelfish
J. P. Gosse, 1963 Distribution:
Distribution: Endemic to the Amazon, Rupununi, and Essiquibo Rivers
Distribution: This is the most widely distributed species in the genus, ranging throughout the rivers, tributaries and flooded areas of the Amazon Basin. The major rivers include the Amazon, the Ucayali in Peru and Solimões of Brazil and Peru, the Amapá river and its tributaries in Brazil, the Oyapock River in French Guiana, and the Essequibo River in Guyana.
It is found in clear, soft, acid, tannin-stained black waters, such as those found in the Rio Negro as well as murky, silted, hard waters of many other other Amazonian hydrosystems.
Although P. altum and P. leopoldi are occasionally available to aquarists, almost always as wild caught imports, what are typically available are variations of P. scalare. These variations are the results of mutations that have been isolated and selectively bred to include traits such as marbled, zebra, lace, gold, platinum, calico/koi/sunset, pearlscale, black, half-black, the recent Philipine blue, and all of the long-finned veil and super veil types.
It is worth noting that there are locales of P. scalare that express unique, identifying phenotypes, such as P. scalare ‘Peruvian’, which is a slightly more vertically elongated version of the nominal form, and P. scalare ‘Manacapuru River’, which also resembles the nominal form, but develops orange/red “shoulders” as it matures. The different locales and even species can be interbred; however, the prevailing sentiment is to preserve genetic purity and keep them separate.
Selective Breeding of Pterophyllum Scalare
To date, 9 different loci and 13 mutations have been identified in P. scalare that can affect its appearance. These have been isolated and selected for various traits to come up with the different phenotypes that exist in the aquarium trade today. They are as follows:
Dark Locus Alleles:
D – “dark” black/melanistic.
Dm or M – “marble” large patches of black pigment against a light background instead of stripes.
Dgm – “gold marble” (aka ‘Gm’) clumps black pigment into smaller and more sparse patches.
dng – “new gold” (aka ‘g’) is total xanthism, allowing the underlying gold colour to show.
Stripes Locus Alleles:
S – “stripeless” removes the four vertical stripes in a single-dose and causes (partial) leucism in a double-dose.
Sze – “zebra” (aka ‘Z’) adds a fifth stripe to the body in the middle of the existing four.
Note: Sze has the same effect on appearance in either one or two doses.
Sm – “smokey” partially or totally reduces the iridescence of the fish, resulting in a duller appearance.
Philippine Blue Locus:
pb – “Philippine blue” in a double-dose ramps up the iridescence of the fish, resulting in shiny blue hues, or platinum fish when it is combined with a double-dose of gold.
h – “half-black” in a double-dose causes melanism in the back half of the body, where scales from the third vertical stripe through to the end of the tail go black.
ps – “pearlscale” in a double-dose ripples the scales in a to give them a diamond or pearly appearance.
St – “streaked” is a subtle mutation that adds flashes of white to the unpaired fins.
a – “albino” in a double-dose reduces all pigment levels causing colourless scales and red eyes.
V – “veiled” is a co-dominant mutation that extends the length of the fins.
Wild-type: + (This is the default gene at all loci unless specified)
Black Veil Angelfish
These glorious angelfish are the spectacular results of the double expressions of both the “Dark” locus allele and the co-dominant “Veiled” locus allele (D/D, V/V). The increasingly hard-to-find “Double Dark Super Veils”! These have always been my favorite of the all of the P. scalare phenotypes.
Below is a video of a pair preparing a site for spawning.
Below, battle-scarred from defending their territory, another pair of black-veil angelfish corral and protect their newly free-swimming brood against the inhabitants of a 65 gallon community aquarium.
 http://theangelfishsociety.org/ Phenotype Library