NEWS103
22
Around40 cm long
Polypterusansorgii
in theaquarium.
Lexicon
Bichirs
Polypterus:means“withmany fins”.
ansorgii: inhonor ofWilliam John
Ansorge (1850-1913).
bichir: from theArabname for the
fish inEgypt.
live specimens of this species in order to
studythemmoreclosely.Unfortunately fora
long timemy effortsweren’t crownedwith
success. Usually the fishes traded as
P.
ansorgii
were
P.bichir
,a close relativeof this
species. But then I obtained four
Polypterus
fromAquariumGlaser’s supplier inGuinea,
FouadChaloub, twoofwhichwerewithout
doubt
P.ansorgii
.The fisheswerearound25
cm long.Thatwas inwinter 2010.The fishes
continue toenjoy thebestof healthandby
now have grown on to around 40 cm in
length.
Polypterusansorgii
growbig!
The similarity between the Guinea Bichir
and
P. bichir
is enormous. Essentially these
fishes can be distinguished only by their
color pattern. While
P. bichir
exhibits a
longitudinal stripepattern,
P.ansorgii
has a
patternof rectangular spots (checkerboard
pattern)on its flanks.
It was to be expected from this obviously
close relationship that
P. ansorgii
wouldn’t
be a dwarf species but similar in size to
P.
bichir
, which grows to more than 60 cm
long. A further indication that
P. ansorgii
grows large is that despite their 40 cm of
length my fishes aren’t yet definitely
sexable (in all
Polypterus
species sexually
mature males can be recognized by the
greatlyenlargedanal fin).
AndnowFouadcreateda real sensation.He
sentusaphotoof an86-cm-long
P.ansorgii
that he and his team had caught in the
River Koliba, a tributary of the River Corbal
near a town called Gaoual – that is,
topotypicalwith the type specimensof the
GuineaBichir.Unfortunately the fish lost its
lifeasa resultofanaccident.Nevertheless it
providedunequivocal proof that
Polypterus
ansorgii
is one of the largest of all the
bichirs.
TheGuineaBichir in theaquarium
The maintenance of
Polypterus ansorgii
in
the aquarium is easy. They are very quiet,
rather shy,andverypeacefulpredators.Like
allbichirstheytendtobecrepuscular fishes,
which, however,will also come out to feed
in the daytime once they have settled in.
They are best fedwithwhole, deep-frozen
fishesaround6-8cm in length (Stint).
Guinea Bichirs are indifferent towards
conspecifics and fishes of other species.
Only at feeding time do they jostle one
another now and then, but this seems to
happenmorebyaccident– thesearescent-
oriented fishes inwhich sight plays only a
subordinate role. I keepmy fishes together
withAfricanPikeCharacins (
Hepsetusodoe
),
a West African lungfish (
Protopterus
annectens
),andanumberofcatfishes.A red
jewel cichlid (
Hemichromis
sp.), originally
introduced as a feeder fish, tyrannized the
bichirs to suchanextent that they stopped
feeding for a number of weeks, until the
little thug,whichmeasured barely 8 cm in
length, could finally be caught and
removed.So it isnecessary tobesomewhat
carefulwhenchoosing tankmates for these
gentlegiantsamong fishes.
All in all it is once again thanks to the
aquariumhobby that apuzzlemore thana
hundredyearsoldhasbeen solvedand the
Polypterusansorgii
myth laid to rest.
