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It is exciting to have a new angelfish variety, especially
since it has been many years after the last angelfish mutation
of merit was found. In recent years new types of angelfish have
been produced by making various combinations of already existing
mutant genes rather than being due to a new mutation. Pearly is
a new mutation that causes a gold angelfish to glitter over most
of its body, very unlike any other angelfish.
Fig. 1: Pearly angelfish.
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| Fig. 1: Pearly angelfish. |
I first heard of pearly angelfish when I received a letter from
Kamphol Udomritthiruj of Seattle, Washington, in October, 1988.
He wrote that he encountered this new angelfish for the first
time in the fish markets of Bangkok during the summer of 1987.
These fish were being called "pearlscale." He added, "then, they
were very sparse and expensive, indicating they were being
brought into the market for the very first time. However, the
expected introduction of this strain did not manifest itself in
America and, peculiarly, upon my return to Bangkok this summer
('88) found them still to be few (too few for such a potentially
commercial strain). The appearance is one of tight convolutions
of the skin/scales giving the highly reflective appearance of
shimmering striations. The pearlscale angelfish that are
available are veiltail and standard golds---." He sent me
photographs of these angelfish, which look like pearly angelfish
that I have.
Tim Anderson, a tropical fish wholesaler and angelfish breeder
in Eagle Grove, Iowa, imported some pearly angelfish from
Bangkok early in 1989. These were called "Pearlscale" but,
subsequently, the supplier changed the name to "pearly" to avoid
confusion with the pearlscale goldfish. Mr. Anderson gave me two
of the fish, which were about silver dollar body size (Fig.1).
When they grew to breeding size, both were discovered to be
females. I crossed one of these females with a gold (non-pearly)
male; this produced 153 non-pearly offspring. Later, some of Mr.
Anderson's pearlys developed into males, making possible a
mating of pearly x pearly. Mr. Anderson told me that these
matings produced 100% pearly offspring. He counted several
spawns: 276, 197, and 131.
Because the pearly trait did not appear in the offspring of an
outcross (pearly x non-pearly) and because pearly parents
produced all pearly offspring, it appeared that pearly is due to
a recessive gene. This was confirmed when I counted an F2 spawn:
162 non-pearly, 56 pearly. This is the expected 3:1 ratio if the
gene for pearly is recessive.
No difference was seen in growth rates of pearly and non-pearly
angelfish. The pearly character becomes evident in fish that are
about nickel to quarter body size. Most dime body size pearlys
have little or no pearly development.
Fig. 2: Close-up of gold angelfish adult, without pearly character.
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| Fig. 2: Close-up of gold angelfish adult, without pearly character. |
The body of a non-pearly angelfish (Fig. 2), which has a flat
surface, is very reflective when front light strikes the fish at
a 45 degree angle to the plane of the body, the light aimed from
the rear of the fish. The fish is non-reflective when front
lighted at a 45 degree angle, aimed from the front of the fish.
Thus, a non-pearly angelfish appears either shiny or dull
depending on how it is lighted.
Fig. 3: Close-up of pearly angelfish adult.
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| Fig. 3: Close-up of pearly angelfish adult. |
The pearly angelfish, (Fig. 3) has wavy rows of convex scales,
creating a bumpy surface. When front-lighted from any angle, the pearly's body has many tiny surfaces that reflect light,
resulting in the fascinating sparkle over the entire body.
The pearly angelfish is unusal enough and beautiful enough to
become one of the staples in the angelfish trade and a wonderful
addition to the tropical fish hobby.
Literature Cited
Ash, Charles A. The new marble angel. The Aquarium 2
(No. 3):4. 1969
Norton, Joanne. Angelfish - breeding and genetics.
The Aquarium 6(No. 10): 34-41 1971.
-----. Angelfish genetics. Part One. Freshwater and
Marine Aquarium 5(No. 4): 15-18, 90-91. 1982a.
-----. Angelfish genetics. Part Three. Freshwater and
Marine Aquarium 5(No. 7):8-10, 91-92. 1982b.
-----. Gold marble angelfish. Freshwater and Marine
Aquarium 11(No. 9):88-90. 1988
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