Page 335 - Encyclopedia of Aquarium and Pond Fish, 3rd Edition

GOLDFISH 333

Carassius auratus
Comet
This elegant variety originated in the United Comet The Comet’s
States during the late 1800s. It is distinguished by caudal and dorsal fins
its slim, streamlined body and its deeply forked are greatly enlarged.
caudal fin, which should be longer than the body This individual
when fully extended. Comets are usually displays some
variegated in color; the most popular variety chocolate body
patterning.
is the Sarasa, which is easily recognizable by the
deep red-and-white patterning extending over
the body and fins. Comets are active by nature
and require a spacious aquarium if kept indoors.
They will thrive in pond surroundings, although
they may prove vulnerable to fin congestion
during periods of severe cold weather.
Variegated dorsal fin
Clear demarcation
between colored
and white areas

Sarasa Orange may replace the more
common red color of these fish. The variegated
patterning differs widely between individuals.

PIGMENTATION AND SHEEN

The protective scales on a goldfish form part of
the outer layer of the body known as the
epidermis. Beneath this is a layer called the
dermis, which itself overlies layers of fat and
muscle. Distributed among these layers are the
pigments that give goldfish their vibrant skin
colors. These include reddish-orange and
yellow pigments known as lipochromes,
and melanin, a black pigment. Lipochromes
usually occur in the upper layers, but the
location of the black pigment is more
variable. If melanin is present just below the
scales, the goldfish looks jet black; if located
in the lower layers, the fish looks blue (for
example, the Blue Pom-Pon, bottom right).
When both types of pigment are present in
different layers, this creates chocolate or
coppery shades. A goldfish that completely Matt coloration extends
lacks pigmentation is silvery in color. over the entire body
Another factor influencing the appearance
of goldfish is the presence in the dermis of the appearance of the goldfish, resulting in a kind
cells known as iridocytes. These cells are of mother-of-pearl sheen. Such individuals are
normally distributed over the entire body, described as nacreous. Shubunkins, for example,
giving goldfish, such as the Blue Pom-Pon, are nacreous goldfish (see p.335).
a shiny appearance. However, the upper iridocytes When the iridocytes are totally absent, a matt
are missing in some goldfish varieties. In such appearance results, as typified by the Black
cases, the lower level of cells has a direct effect on Moor shown above.

ORIGINS Asia, originally from SIZE Highly variable; often DIET Goldfish food (flakes WATER Temperature 50–77°F TEMPERAMENT Relatively
waterways in southern China. exceeds 12 in (30 cm) in ponds. or pellets) and live foods. (10–25°C) and neutral (pH 7.0). social, but does not shoal.

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