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Reprinted
with permission from:
Dr. Joanne Norton
Freshwater And Marine Aquarium
magazine
Black Velvet
Angelfish
Photos and Text
by Dr. Joanne Norton
FAMA: July 1984; Vol. 7, #7
Figure 1: Juvenile black having one
dose of dark
and one dose of marble.
Figure 2: Juvenile black velvet (two
doses of stripeless,
one dose of dark, one dose of gold).
Black Velvet
Angelfish
The first black
angelfish were obtained from black
lace parents in the 1950s. These
blacks, which I call "true black,"
have two doses of the genetic factor
for dark, whereas black lace have only
one dose of dark. True blacks have
faint vertical body stripes, which can
be seen by shining a flashlight at the
fish.
It was not until the
late 1960s, after the marble angelfish
became available, that another type of
black angelfish was possible. This
black has one dose of dark and one
dose of marble (Norton, 1971). The
black marbled pattern on a dark gray
background is evident in juveniles and
can be detected in strongly
illuminated adults. The genetic
factors for dark and marble are
alleles (Norton, 1982a).
The third type of
black angelfish to appear is one that
has one dose of dark and one dose of
"new gold," which is an allele of dark
and marble (Norton, 1982a). The
genetic factor for "new gold" which I
shall refer to as "gold" in the rest
of this article, increases the
expression of both dark and marble
(Norton, 1982a). A black angelfish
having the dark-gold genetic makeup
has a somewhat brassy body color and
fairly obvious vertical stripes on the
body.
The newest and best
black angelfish, which I call "black
velvet," is the same, genetically, as
the dark-gold type, but in addition it
is blushing. That is, it has two doses
of stripeless (making blushing) along
with one dose of dark and one dose of
gold. Black velvet is the same
genetically as "blue" with the
addition of one dose of gold. The
black velvet angelfish is a smooth,
velvety black with no stripes.
Fig. 3: Adult male blue angelfish (two
doses of stripeless,
one dose of dark). Black velvet is the
same, with the
addition of one dose of gold.
There are two other
types of black angelfish without body
stripes. One is a true black (two
doses of dark) that has been raised in
continuous light instead of with the
lights turned off at night (Norton,
1982b). The other is a true black with
one dose of stripeless. True blacks
are low in vigor, slow-growing, and
have a high mortality rate of the fry.
Therefore, true blacks should be
replaced by more vigorous black, which
have only a single dose of the genetic
factor for dark.
Parents having the
dark-marble genetic makeup will
produce offspring in the ratio of 1
true black: 2 black (dark-marble
genetic makeup): 1 double-dose marble.
Thus, only 50% of the offspring will
be good blacks. The true blacks and
double-dose marbles are slow-growing
and have a high mortality rate. There
are three kinds of fish to sort.
Sorting and slow-growing runts can be
avoided by crossing a double-dose
marble with a true black. This cross
will produce 100% of the desired
dark-marble genetic makeup (Norton,
1982a). The disadvantage of this cross
is that it requires the maintenance of
two low-vigor lines, the true black
and the double-dose marble.
Using parents that
have the dark-gold genetic makeup will
produce offspring in the ratio of 1
true black: 2 black (dark-gold genetic
makeup): 1 gold. There will be three
types of fish to sort, including the
true black runts. Better results are
obtained from a cross of gold and true
black, which will produce 100% of the
vigorous type of black (one dose each
of dark and gold). A ratio of 1 gold:
1 black (dark-gold genetic makeup) can
be obtained by crossing a gold with a
dark-gold type of black. The
disadvantages of the dark-gold type of
black are its brassy color instead of
deep black and its body stripes.
Adding one dose of
stripeless to the dark-gold type of
black will eliminate the body stripes.
However, in doing this you would have
to maintain two separate lines (one
blushing, one not blushing) for the
breeders.
Fig. 4: Adult male black velvet
angelfish. He is a
blushing (two doses of stripeless)
with one dose of
dark and one dose of gold.
The body stripes of
the dark-gold type of black can be
eliminated by two doses of stripeless
(blushing). The advantage of this
method is that only one line of
breeders is necessary. Crossing a gold
blushing (two doses each of gold and
stripeless) with a black velvet (two
doses stripeless, one dose of dark,
one dose of gold) will produce 50%
black velvet and 50% gold blushing.
This production of only two types of
offspring can continue generation
after generation by always crossing a
gold blushing with a black velvet.
My original black
velvets were obtained from a clown
female (clown:
see Norton, 1983) that had one
blushing parent; therefore, this
female had one dose each of dark,
zebra and stripeless. This female,
crossed with a gold blushing male,
produced a spawn containing some black
velvets.
To decrease
inbreeding in the black velvet line,
you could introduce a gold blushing
from another source. But, this may not
be necessary if you always select the
most vigorous and fast-growing young
to save for your next breeders. Some
commercial producers make the mistake
of sorting a spawn, taking the largest
individuals to sell, and leaving the
smaller ones to grow more for later
use. Then slow-growing fish end up as
breeders because they are the only
ones available.
Fig. 5: Adult female black, having one
dose of dark
and one dose of gold.
Comparing the
advantages and disadvantages of the
various types of black angelfish, I
feel that the black velvet is the best
for commercial production, the home
aquarium, and showing. The true black
may have somewhat deeper color than
the black velvet, but it is
undesirable because of its low vigor
and poor reproductive ability. The
black-marble type has the disadvantage
that it is produced best from two
strains that are not robust fish. The
dark-gold type of black is produced,
if desired, from one strain, but its
color is not very good. Black velvet,
produced the same as the dark-gold
type of black, has better color.
Although the black
velvet angelfish is obtained from
mixed spawns of 50% black velvet and
50% gold blushing, at least these two
types are easily distinguished at any
age and are relatively easy to sort.
Also, their sorting is not interrupted
by fading of color, making it
necessary to stop sorting until the
colors come back (as happens with
black lace, for example). A distinct
advantage of the black velvet is that
only one strain is required to produce
it. Black velvet crossed with gold
blushing will produce black velvet and
gold blushing offspring in about equal
numbers. The strain "breeds true" in a
sense, producing only two types of
offspring.
Literature Cited
Norton, Joanne. Angelfish-breeding and
genetics. The Aquarium 6(10):34-41
1971
Norton, Joanne. Angelfish genetics.
Part three. Freshwater and Marine
Aquarium 5 (7):8-10 et seq.
1982a.
Norton, Joanne. Angelfish genetics.
Part six. Freshwater and Marine
Aquarium 5(10):38-40. 1982b.
Norton, Joanne.
Clown angelfish. Freshwater and
Marine Aquarium 6(5):15-17 et seq.
1983.
Leopard Angelfish
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