Page 169 - Encyclopedia of Aquarium and Pond Fish, 3rd Edition

LIVEBEARERS/GUPPIES 167

Poecilia reticulata
Endler’s Livebearer

ORIGINS South America, where this attractive wild form
of the Guppy is found in parts of Venezuela.
SIZE 2 in (5 cm).
DIET Prepared foods and small live foods.
WATER Temperature 70–77°F (21–25°C); hard
(100–150 mg/l) and alkaline (pH 7.5).
TEMPERAMENT Peaceful and social.
These spectacularly colored fish are a wild form
of the guppy. Despite this, Endler’s Livebearers
must not be housed with guppies, because they
hybridize readily with them and soon lose their
distinctive characteristics. The body colors of
Endler’s Livebearers range from blues and greens
through to oranges and reds. These fish are prolific
breeders, but they have a relatively short life span
of no more than a year.

Selective breeding of Tuxedo Multicolored Delta Guppy The tuxedo
guppies began during the characteristic (the black area toward the rear of the
1950s, but unfortunately, a body) can be combined with different colors to striking
number of strains—even some effect. This variety also has the broad delta-tail.
that are carefully maintained—are
not stable. This means that many of the resulting THE GRAVID SPOT
offspring may not display the most desirable
characteristics of their parents. Cobra patterning is
one of the most stable characteristics in terms of Breeders of popular livebearers have relied
markings. This is a dominant genetic characteristic, on the appearance of the dark gravid spot to
so well-marked individuals are always likely to pass indicate that a female is about to give birth.
their cobra patterning on to the next generation. This spot is formed by the dark lining of the
However, recessive characteristics, such as tuxedo Relatively even, abdomen, known as the peritoneum, which
patterning, may disappear for several generations blackish tip on the bulges against the sides of the female’s body
of a particular bloodline and then reemerge broad caudal fin just before she gives birth, pushed out by the
unexpectedly at a later stage. increasing size of her brood. The gravid spot
is less apparent in swordtails, simply because
Blue Tuxedo Guppy This particular variety is also the female’s abdominal wall is more muscular.
described as the Blue Delta-Tail Half Black, based on its
body coloration. The broad caudal fin is predominantly Once the gravid spot has appeared, the female
blue, with variable black markings. should not be moved; otherwise, she is likely
to abort her brood.

Irregular patterning
running across the
caudal fin
Flamingo Guppy The breeding trend with this strain has Green Variegated Delta Guppy Like other guppies with
been to improve the depth of the red coloration. Early a delta-shaped caudal fin, the Green Variegated Delta
examples were considerably paler than those being bred Guppy is a slower swimmer than sleeker-tailed forms.
today. Flamingo Guppies are also called Golden Redtails. This variety should be housed in a single-species tank.

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