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Withquiveringmovements the female then
depositsoneormoreeggs in thesamespot,
turns around, and takes the eggs into her
mouth. The male now swims back to the
spawningsiteand releasessperm,which the
female takes intohermouthwith the eggs,
where fertilizationtakesplace.Onlyrelatively
few - around30–eggsare laid,but theyare
comparatively large. The individual
spawningstagesalwaysfollowthesequence
described, ie cleaningby the female, sperm
releasebythemale,collectionofeggs,sperm
releaseby themale.
The
female
now
performs
the
mouthbrooding for around 10-12 days, but
constantlyremains inthevicinityofthemale.
After this period she transfers the spawn to
the
male,
who
completes
the
mouthbrooding for a further 7-10 days.
There is no ongoing brood care of the fry
after release. All Tanganyika Clowns exhibit
this behavior, with the exception of
Spathodus
marlieri
,
which
practices
exclusivelymaternal mouthbrooding (ie by
themother).
Sexualdimorphism
Amajor problempreventing the successful
breeding of Tanganyika Clowns in the
aquarium is that the sexes can be
distinguished only with considerable
difficulty, but on the other hand the high
degree of intraspecific aggression doesn’t
allow maintenance in a group. Essentially,
femalesalways remain smaller,so ifpossible
you should select the largest and the
smallest individual from a group. Plus pairs
will often alreadybe swimming together in
thedealer’s tankandyoucanworkoutwho
goeswithwhombywatching.
But color differences can be seen in some
populations; thus the females of many
Eretmodus
populations are darker colored
than the males. In some populations of
E
.
sp.“CyanostictusNorth”thefemaleshave less
blue on the head. In the population of
Tanganicodus irsacae
from Ikola the females
haveabroadercoloredmargin to thecaudal
fin.And in
Spathodusmarlieri
malesdevelop
anuchalhump.
References:
KONINGS,A.(1999):TanganyikaCichlids intheir
NaturalHabitat.CichlidPress,ElPaso,USA.
TAWIL, P. (2005): Les cichlidés gobies ou
éretmodines.Nouvellesespecèsen
provenance de la côte ouest du lac
Tanganyika.LanCichlidé,Vol.5.
Largephotomale, small photo female
Tanganicodus irsacae
from Ikola (Tanzania).
Lexicon
TanganyikaClowns
Eretmodus:means“withoar-like
teeth”
Spathodus:means“with sword-like
teeth”Tanganicodus: refers to the
fact that thegenus comes from
LakeTanganyikaand is
distinguished from theprevious
twogeneraby its teeth (ancient
Greekodousmeans“tooth”).
cyanostictus:means“withblue
spots”
erythrodon:means“with red teeth”
marlieri: inhonor ofG.Marlier, the
former headof the IRSAC research
station inUvira.
irsacae: from the IRSAC research
station inUvira.
Male
T. irsacae
.Note thedorsal-fin spot typical
of thegenus.
Photo:Hans. J.Mayland /Aqualog
Astonishingly juvenile
Eretmodus
are
sometimes sexuallydichromatic,withmales
darkand females light incolor.
All in all, Tanganyika Clowns are gorgeous,
easy-to-keep fishes, whose successful
breeding in the aquarium nevertheless still
representsachallenge.
