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CHAPTER 2

Angelfish Groups

There are a number of learned ichthyology books and papers, as well as a great number of Web sites, about what are called the meristics of angelfish—scale and fin counts, minute measurements of the lateral line, and other anatomical details. Most hobbyists (and I include myself in this group) are not much interested in these arcana, and I will not go into them here. If you are interested in the in-depth study of angelfish, a list of Web sites is provided at the end of this book. For now, a basic discussion of angelfish characteristics is in order.

THREE SPECIES OF ANGELFISH

Dr. Sven Kullander of the Swedish Museum of Natural History in Stockholm has done the most recent, and so far the definitive, work of classifying the species of angelfish. Today it is generally accepted that there are three species of angelfish, collectively assigned the genus Pterophyllum. The three species considered valid by Kullander are P. scalare, P. altum, and P. leopoldi. According to Kullander, Pterophyllum scalare are sometimes referred to as P. eimekei and P. dumerilii, names he rates as “junior” synonyms, which means that fish called by these names are, in fact, P. scalare and that the first published name (in this case, P. scalare) takes precedence over the names that were published later. (The other two species names, P. altum and P. leopoldi, are considered valid by Kullander. For excellent documentation of the history of scientific nomenclature of the angelfish, see http://www.finarama.com/tba/timeline.htm.)

A P. scalare angelfish displays its silver coloring with hints of blue. This species is the original angelfish, and all of our modern color varieties were developed from it.

Scientific names are traditionally given by the scientist who first describes a species and are often revised by followers in the profession of ichthyology. Often, the scientific name is chosen to honor the discoverer of the fish or a friend or relative (lots of fish are named for the namer’s wife, to placate her for putting up with a fish nut). Sometimes a fish species is named for the location where it was discovered. Finally, a species name may describe some characteristic of the fish. This is the case with the angelfish. The name of the genus Pterophyllum comes from the Greek and means “winged leaf,” referring to the overall impression that the angelfish gives of floating through the water. The species name scalare means “staircase or flight of stairs,” describing the front edge of the dorsal fin as it ascends from the forehead of the fish in steps to the tall top of the fin.

The black lace, shown here, was one of the first color variations of angelfish to be fixed into a strain that breeds true.

The wild angelfish, from which all of the many color varieties available today come, is a basically silver fish with some highlights of a bluish cast over parts of the body. There are three prominent vertical stripes in all three species, with extra stripes and markings as noted for each species. There are broad distinct black lines running vertically on the fish. The first line runs through the eye, from the forehead down to under the gills. A second line crosses the middle of the body, and the longest and thickest line runs behind that one, from the rear of the dorsal fin down through the rear of the anal fin. Finally, on some fish there is a small black marking around the caudal peduncle, where the tail joins the body.

EVERYONE EASILY RECOGNIZES THE ANGELFISH

The thin body, tall fins, and elegant way of swimming have made the angelfish one of the few fish that everyone knows the name of. Its popularity is well earned, as it makes an excellent aquarium fish. Even beginning hobbyists can successfully keep angelfish if they implement proper care.

A pair of wild altum angelfish swims gracefully.

Angelfish have very compressed bodies that are thin and round. This body type allows angelfish to blend in with their surroundings and to slip in and out of the maze of driftwood where they live and thus avoid predators with much thicker bodies that cannot fit into narrow spaces. The mouth of the angelfish is very pointed, and the eyes are on the sides of the head, but both eyes can focus in front of the fish, which tells us that the angelfish is a good hunter. Anyone who has lost a bunch of cardinal or neon tetras to growing angelfish will attest to their skills as hunters. The ventral fins have become extremely pointed and elongated and are usually referred to as feelers, as with gouramis. The long ventral fins are used to orient the fish in the often murky waters of its natural habitats and are put to excellent use when the fish are spawning and they feel for a surface upon which to deposit their eggs.

Angelfish are very popular fish in the hobby; most people instantly recognize the angelfish’s distinctive shape and know its common name. If your local fish store has a good source, it will usually carry angelfish in a few color varieties and different sizes from smalls to mediums and even to young breeders.

Pterophyllum Scalare

Some angelfish aficionados are of the opinion that the fish currently in the hobby are, in fact, a mélange of different wild angelfish species and hybrids, a position that is not at all unreasonable. Perhaps as DNA sequencing improves we will be able to define the species of angelfish more exactly and learn for sure the precise genetic makeup of the angelfish common in the hobby today. Suffice it to say that, when we refer to angelfish, what we mean is fish that look most like the wild P. scalare, and it seems clear to me that this is the species from which all the variants that we have in the hobby today come. Wild scalares are sometimes available at large fish stores that specialize in cichlids, and some commercial breeders breed wild fish back into their strains for extra strength and vigor, as angelfish can become inbred to the point that many fish will develop genetic deformities and display weakness in general.

Adult scalares usually measure about four inches in length from nose to the caudal peduncle where the tail starts, and at maturity about seven to eight inches tall from the top of the dorsal fin to the bottom of the anal fin. These fish are silver to white in body color with vertical black stripes. Some wild scalares have red eyes, which is considered a desirable trait.

The conformation of this fine marble angelfish is close to being perfect; the rounded ventral fins (“feelers”) enhance the overall proportions of the fish.

Pterophyllum Altum

P. altum is the largest species of angelfish, with very elongated bodies and long trailing fins, including streamers off the ends of the dorsal and ventral fins. The species name altum means “tall” or “high” and refers to the species’ most obvious trait. True altums are distinguished by their strikingly upturned noses and by broad brownish colored bands between the black vertical bands on the sides of their bodies. I have seen altums in a fifty-five-gallon tank that could barely swim without their fins either hitting the bottom of the tank or sticking out of the water; this would make them close to eighteen inches tall. Altums that I have kept myself have never gotten much taller than around ten inches, but they are a much heavier and broader fish than are the other species of angelfish.

Along with their larger size, altums are somewhat more aggressive than other angelfish. All the regular angelfish (which are all scalare descendants) I have ever raised have been peaceable, mostly docile fellows; they hang out together in their tanks and rarely push any of their brethren around. All the altums I have ever had, from when I first got them at the size of a quarter to fully mature adults, are just plain nasty fish. Even as babies, they are always bickering with each other, spacing themselves out in the aquarium so they are as far away from one another as possible. When one fish drifts too near another, there is a small battle, and the entire shoal of altums rearranges itself. This goes on constantly. The adults demand this personal space as well, partitioning themselves out in the tank. Altums tend to be more colorful than regular scalares are, depending on their mood and probably on their foods. For instance, if you feed them foods with a lot of xanthins, the reds in the fish are brought out. When sparring for position in a tank, the fish flares out its fins to try to appear as large as possible, and its stripes darken dramatically. I have some altums that have lovely blue spangles on the region of their head and sometimes almost covering all of the body, with prominent red speckles in places all over the fish.

These juvenile altum angelfish are just beginning to show the high dorsal and ventral fins that gave this species their name; altum means “tall.”

At the present time, altum angels are not produced by any breeder on a regular basis. Altums have a well-deserved reputation for being very difficult to keep and nearly impossible to breed (but then, wild scalares were also impossible to breed at one point in time, so perhaps there is hope with altums). The problem, I fear, is that altums are very rare fish and very expensive, and therefore not many hobbyists are even keeping them, let alone trying to get them to breed. You may be lucky enough to find wild altums in your local fish store on a seasonal basis—they are usually available from August to October.

These altum angelfish are regal fish, with broad brown stripes in addition to the black stripes that scalares have.

However, be aware before buying them that altums are delicate fish, and sometimes an entire batch will die for no apparent reason. Because they are all wild fish, they almost always have parasites, not all of which can be controlled in an aquarium environment. The adult group I have now numbers seven fish, down from fifteen that I originally acquired three years ago. A few were lost as young fish, but in the past year I have had a number of the adults succumb to some sort of internal parasite, which I assume is a form of trematode in the part of its cycle where it has to live in fish (see chapter 6). I have not been able to figure out exactly what the problem is, let alone how to cure it in the fish—another illustration of the difficulty of keeping altums.

It is easy to see from this picture why P. leopoldi is often called the “football” angelfish; because of its shape, many people do not find it as attractive as they find the strains developed from P. scalare.

SCIENTIFIC NAMES CAN BE CHANGED

The taxonomic status of angelfish will, I imagine, be subject to change in the future. It seems that ichthyologists make their bones by constantly revising the work of their predecessors, and I presume that Kullander is no more immune to this than were those who came before him. Of course, it really does not make much of a difference to us when it comes to the angelfish we can purchase at our local fish store.

Pterophyllum Leopoldi

P. leopoldi is the smallest of the wild angelfish species. The leopoldi are usually no more than four inches long, total length snout to tail, and four to five inches tall from the top of the dorsal fin to the bottom of the anal fin. This angelfish is also generally squatter than the other two species and is hence sometimes referred to as the football angel. I have not seen this fish in any local fish store for many years, perhaps because it is simply not very attractive.

Crossbreeds

All angelfish will readily crossbreed, and there are many examples of wild fish that are clearly naturally occurring hybrids of two of the recognized species (scalare and altum). The most common possible wild hybrid fish is what is foisted off on hobbyists in local fish stores as Peruvian altums. Although it may, in fact, have some altum blood, this fish is really just a scalare with a slight upturn to the nose. The idea that angelfish crossbreed is confusing if you accept that part of the definition of a species is that its members won’t breed with fish that are not their species, but species crossbreeding also occurs with the cichlids from Lake Malawi in Africa. Sometimes, if the choice is between passing on your genes by breeding with a species you may not be sure of but who looks enough like you that it could be a conspecific or not passing on your genes at all, there is only one thing to do. Most tropical fish aren’t that finicky about minor points such as the definition of what a species is, and so we get wild natural hybrids—but in the hobby we also get monstrosities such as the bloody parrot cichlid and the Flowerhorn. (Sorry, I let my biases slip.)

ANGELFISH “FLAVORS” AT YOUR LOCAL STORE

Let’s look more closely at the different types of angelfish you are likely to find in your local fish store. In my wholesale business, I refer to these as the different flavors that angelfish come in. The first successful breeding of angelfish was in the 1920s, and for many years everyone was happy just to be able to breed the wild fish, known as silvers, then the F1s (first generation of progeny) from the wild fish, then the next generation, and so on. When I first started keeping angelfish in the 1960s, a few new strains were just being introduced. These were developed from wild fish with genetic mutations that affected their appearance and from selective breeding that sought to introduce or emphasize some variant characteristic in subsequent generations. The first new types of angelfish were what are called black lace—fish with a grayish dark cast to the body rather than the pure silver of the wild fish. There were also marbles, which are fish with a random mottling pattern of black and white all over the body and fins.

The August 1923 cover of Aquatic Life magazine demonstrates the popularity of angelfish, as they are shown alongside easily recognized fish of the day. The cover remained the same from 1916 through the mid-1940s.

In addition to the black lace, breeders soon came up with a pure black angelfish. This fish, at the time of its first appearance in the hobby, was as difficult to keep as it was beautiful and virtually impossible to breed; apparently the genes that make this angelfish pure black also make it a very weak fish. Today’s black angels are really what are called double darks; they do not have the lethal gene of the original, but they are not the midnight black that the original black angels were. Soon we had other strains of angelfish, including the gold, the pearlscale, and the koi, all of which are very popular in the hobby today.

As mutations of coloration were cultivated in different strains of angelfish, selective breeding also developed angelfish with longer fins, leading to what are called veiltails, consisting of very long and flowing fins. The veiltail trait has been taken to the extreme in the varieties known as heavy or double veiltails. These fish have such heavily veiled fins that they are, to many people, unattractive. And the heavy fins have functional disadvantages: they make it difficult for mature double veiltail angelfish to swim. The fish drag their fins along the bottom of the tank, which leads to all sorts of problems with tearing of the fins. This, in turn, leads to fungus problems and other maladies. Fortunately, the heavily veiled fish are rarely seen today in the local fish stores, and they appear to have only a minor presence among the serious angelfish hobbyists.

These angelfish demonstrate the wide variety of fish that are available in the hobby; one fish is solid black, whereas the other is a solid gold coloration.

Several strains of the fish mentioned above are now commonly available throughout the hobby. We will take a look at each of the most popular strains below.

Silver

The normally occurring coloration of the wild angelfish is a silver body, sometimes with a bluish cast; distinct vertical stripes running through the eye, the center of the body, and the rear of the body into the dorsal and anal fins; and often a stripe at the caudal peduncle, where the tail joins the body. Silvers used to be the strongest fish because they were the closest to the wild fish, but angelfish today have been so interbred that the silver angels you can get at your local fish store today are no hardier than any other variety. Silvers are, however, usually the least expensive of the varieties, and they are certainly the most commonly available at your local fish store.

This young silver angelfish is perfectly proportioned and will grow into a fine adult, perhaps even one of breeding quality.

Marble

The entire marble fish is colored in uneven speckles of black and white (silver). There are heavy and light marbles, depending on whether there is a lot or a little black on the fish—the blacker fish are considered heavy marbles. There have been many attempts to fix the marble pattern, including those by yours truly, but no one has ever been able to produce a regular pattern of the marbling. I had some marble angels that had heavy marbling at the head and tail of the fish, with the middle of the body being almost clear. I worked for a while on fixing this trait in the fish but was unsuccessful.

This marble angelfish belongs to a very hardy and popular strain of fish.

This double dark black angelfish is a sturdy fish and does not have the problems of lethal genes common in the early strains of black angelfish.

ANGELFISH STRAINS

By selective breeding, commercial fish farmers and individual hobbyists have developed all of the different strains of angelfish in the hobby today. New strains have not been developed in recent years, and we may have exhausted the genetic variations possible for angelfish. Breeders continue to improve the existing strains, especially the koi and gold angelfish.

Black

These angelfish are almost completely black, although to avoid the lethal genes of the early black angelfish, today’s blacks have a slight shading of less than pure black. These fish are often referred to in the hobby as double dark black to differentiate them from the black angels carrying lethal genes.

Black Lace

As we have discussed, the black lace was one of the first mutations to be fixed into a strain, and it consists of a dusting of dark gray all over the fish. The black lace trait occurs in varying degrees; some fish are just slightly dusted, and others appear almost black.

Blushing

This fish, also called stripeless, is basically a shiny gray color. The name blushing comes from the fact that the gill plates lack color, allowing the red of the gills to show through. Blushing angels have never been particularly popular fish in the hobby, although they are still widely available at local fish stores.

Gold

This is a solid yellow-gold fish. The gold angelfish appears in many shades, ranging from a bright yellow to a deep reddish orange. Every so often someone comes up with a new strain of special gold angel, such as the Naja Gold, but these fish have not taken hold in the hobby, although I think their genes have led to the development of the koi angelfish that are so lovely and abundantly available now.

This gold angel shows the purity of color typical of this variety, with the beginning of darker gold-orange on the head.

Gold Marble

This is just what it sounds like, a golden fish that has marbling on its body. Gold marbles, like plain marbles, are available with varying amounts of the black marbling on the fish. My experience has been that gold marbles are one of the strongest angelfish available, which makes sense, as they have many different strains of angelfish in their background and therefore possess a great deal of what is called hybrid vigor.