(Not counting Lichtenstein's 1821
paper, which went unnoticed for many years; Lichtenstein
described an angelfish under the name Zeus scalaris.)
The first freshwater angelfish known to science was described
in 1831 by Cuvier & Valenciennes in Histoire
Naturelle des Poissons. They named the fish, which was
described from a preserved specimen, Platax scalaris,
since to them it appeared to be related to the batfishes of the
marine genus Platax, which aslo have very tall and deep dorsal
and anal fins. Later, in 1839, the fish was renamed by Heckel,
when it was realized that it belonged to the family Cichlidae.
The new name was Pterophyllum scalare (pronounced TER
O FILL' UM SKA LAR'E). As with many other scientific names,
the meaning is interesting and quite descriptive.
Pterophyllum means "winged leaf" and is derived from
Greek, while scalare means "like a flight of stairs"
in reference to the dorsal fin. It is a Latin word, and can also
mean "ladder.
"The first living angelfish were imported into Hamburg,
Germany in 1911, and a short while later, specimens reached the
United States. Dr. George S. Myers recalled that when he first
saw them in 1917 they were extremely scarce, and adult fish were
selling at a price of $75 for two, with no guarantee of sex.
Finally they were spawned in Philadelphia, which in that time
was considered by many to be the center of fish keeping in the
U.S., by a gentleman named Paullin. The prices, however,
remained prohibitively high, although the aquarium-raised
specimens quickly sold out. In 1922 and 1923 there were large
importations of angels to the U.S. from Germany, where breeders
had been successful in propagating them, and this brought the
price in America down substantially. The greatly increased
availability also resulted in breeding success in the U.S.,
further increasing availability.
About 1927 an angelfish
called Zwergscalare (dwarf scalare) appeared in Germany; this
fish had been imported from the Amazon. The importer's name was Eimeke, and in 1928
Dr. Ahl of the Berlin Museum described the
fish as a new species, naming it Pterophyllum eimekei in honor
of the importer. Another angelfish, Pterophyllum altum, had been
described from the upper Orinoco in Venezuela in 1903. This is
the largest and deepest-bodied of the angels and has been
occasionally imported in recent years. This is quite an
impressive show fish, although it apparently has not been
spawned in the aquarium. The other species so far recorded was
described as Plataxoides dumerilii by Castelnau in 1855.
This
fish as described had the shallower body which distinguishes P. eimekei from
P. scalare and P. altum for the most part in
appearance. It is known that the two fishes known as
Pterophyllum scalare and Pterophyllum eimekei will interbreed
and that the resulting offspring breed successfully. It may well
be, and has been suggested, that the angelfish of the aquarium
hobby today are for the most part a mixture of the two and that
very few, if any, pure P. scalare or P. eimekei are kept by
aquarists. It has also been suggested that P. eimekei
may not be
a species distinct from P. scalare, but simply a variety or a
subspecies. There also exists a possibility that Pterophyllum
dumerilii and P. eimekei are the same species, since the body
shape is so similar. This possibility further clouds the status
of P. eimekei since if they should prove to be the same,
Pterophyllum dumerilii (Castelnau, 1855) would take precedence
over the more familiar name Pterophyllum eimekei Ahl,
1928.Following are descriptions of the angelfish species which
have been seen in the aquarium as they are now understood.
Pterophyllum eimekei (Ahl, 1928)
Popular name: Angelfish, scalare; lesser angelfish
Range: Middle Amazon
For some time, Pterophyllum eimekei was considered to be the
angelfish commonly found in the aquarium hobby and the easiest
to breed. The body depth is not as great as in P. altum or
P. scalare, being found one-and one-half times in the length from
tip of snout to base of caudal fin. The front part of the
lateral line is much flatter and less curved than in the other
two species. The curve of the upper profile of the head is
gentle and even, and there is no deep indentation between the
snout and forehead. There are about thirty-two to thirty-four
scales in a straight series from the upper part of the opercular
slit to the caudal base, according to Myers. Sterba has the
lateral line count at twenty-nine to thirty-six. Myers found P. eimekei to have only twenty-eight vertebrae, while both
P. scalare and P. altum had thirty. Coloration is silvery on the
sides, with a bluish sheen. Upper part of back and nape blackish
brown-yellow with small brownish-red blotches. Gill cover silver
with shining green blotches. Several prominent black transverse
bands on sides, the second, fourth and sixth being most intense
while those between are rather obscure. There is also a band
through the eye. The fourth and most prominent band runs from
the tip of the dorsal to the tip of the anal. Ventral fins are
"feelers" rather steel-blue at bases, bluish-white on extended
portions. Posterior edge of ventrals blackish or dark. The
original importation of the Pterophyllum eimekei was said to
have come from the mouth of the Rio Negro near Manaos, Brazil.
Pterophyllum scalare (Lichtenstein, 1823)
Popular name: Angelfish, scalare
Range: Amazon to Guyana
Pterophyllum scalare is obviously the fish from which the
popular name scalare, originated. P. scalare has a greater body
depth than P. eimekei, the greatest depth of the body fitting
into the length from snout-tip to tail-root one-and-one-eight to
one-and-one fourth time. According to Myers there are
thirty-three to thirty-eight scales in a straight series from
the upper end of the gill-slit to the end of the fleshy part of
the caudal root, while according to Sterba there are
thirty-eight to forty in the lateral line series. Coloration is
greenish-gray to olive gray, with a bright silvery sheen. Back
brownish-olive with reddish-brown or yellowish cast. Sometimes a
reddish-brown blotch in front of and below dorsal. Four
prominent bands on sides with three shorter and less prominent
bands between; all bands are black to dark gray, varying with
conditions. The fifth band is darkest and boldest and reaches
from the tip of the dorsal to the tip of the anal.
Pterophyllum altum (Pellegrin, 1903)
Popular name: Long-finned angelfish, deep angelfish
Range: Orinoco
The body of Pterophyllum altum is much deeper than that of
either P. scalare or P. eimekei. The dorsal and anal fins have
very long bases and are much longer than the other two species.
The forehead angels up very sharply from the snout, which is
strongly concave. The greatest body depth is equal to or greater
than the distance from the tip of the snout to the end of the
caudal root or tail root. The front part of the lateral line,
which is in two parts, is more curved than in the other species.
There are forty-one to forty-seven scales in a straight series
from the upper end of the gill or opercular opening to the end
of the caudal root. Coloration is greenish gray to olive gray,
with a bright silvery appearance. Several bold black bands on
sides, the most prominent of which runs from the tip of the
dorsal to the tip of the anal. Upper part of body with brown
dots, a few brown to blackish blotches on flanks. First
described from specimens in Paris Museum which were from San
Fernando de Atabapo, Upper Orinoco, Venezuela.
Pterophyllum dumerilii (Castelnau, 1855)
This species apparently has not been imported.  |