ThisBlueDempseyhas just swalloweda smaller fish.
And the JackDempseyhasnever diedout
completely in the aquarium hobby. It was
kept going through twoWorldWars, and
the aquarium strains, whose precise
provenance canno longer be ascertained,
became considerably more peaceful
through selective breeding. But the Jack
Dempsey didn’t undergo a real boom
againuntil themiddle of the 1990s,when
suddenly specimens with a brilliant blue
sheen turned up in Argentina and were
christened the "Blue Dempsey". Initially
horrendous prices were demanded - and
sometimes even paid! - for these fishes.
Theusualmythsgrewupandwild rumors
circulated that this fishwas actually awild
form and originated from Argentina. But
there are just as few Jack Dempseys in
Argentina as there are in Manaus. The
species occurs onlyon theAtlantic sideof
Central America (Belize, Guatemala,
Honduras,andMexico).TheBlueDempsey
is simply a mutant, a genetic whim of
Mother Nature,whichwas able to survive
in the aquarium. BlueDempseyswouldn’t
stand a chance in the wild. The fry grow
more slowly than their wild-colored
siblings. And there are always some of
those, as it has turned out that if Blue
Dempseys are mated with one another
they don’t produce any viable young.
Hence inpractice theBlueDempseyhas to
becrossedwith theoriginal JackDempsey.
Thisalwaysproducesapercentageof Blue
Dempseys,but theseneed tobeseparated
in good time from their normal-colored
siblings inorder togrowonoptimally.
have its ending changed frommasculine
to feminine. So now, after more than a
hundred years, the Jack Dempsey at last
has a generally accepted scientific name,
namely
Rociooctofasciata
.
Kin liabilty
Cichlids were already familiar at the
beginning of the 20th century. The
Chanchito (
Australoherosfacetus
),aspecies
from southern South America (Argentina,
Brazil, Uruguay) that is nowadays almost
completely forgotten in the hobby, was a
very popular fish around the turn of the
century, as the heating of aquaria was a
tricky business. Because of its southerly
origins
the
Chanchito
tolerates
temperatures down to just below 10°C, so
that itsmaintenancewaspossibleeven for
those aquarists unable toheat their tanks.
There are in fact supposedly feral
populations of the Chanchito in Spain, in
the River Guadiana, although who
released them, and when and why, is
unknown. The popular name Chanchito
means "littlepig"and isveryapt– it isvery,
very fond of digging. In addition the
species can also be extremely rough
towards other fishes in over-small tanks.
But all this was of little concern to
aquarists, soexcitingwas it toobserve the
brood care of these cichlids - the
Chanchito is a typical open brooder that
spawnson rocksorwood in theopen,with
bothparents tending theeggs, larvae,and
fry. But by the time the Jack Dempsey
arrived thisbehaviorwasnothingnew,and
hence,apart fromabriefperiodofbeing in
fashion in the 1930s, this colorful Central
American faded into the background for
many decades. Quite simply, it was
regardedasmuch toobadlybehaved.
The revival
Nowadayswe know that the extremebad
behavior observed in these fishes was
attributable toexcessively restricted living
space.
Rociooctofasciata
can generally be
keptwithother species in largeaquariaof
around500 litersupwards.Of course,even
here the fishes will guard their offspring
vigorously, but that was always the case.
Male .....
NEWS105
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