Re: apisto life spans (D. filamentosus) -Reply

[raychah@auburn.campus.mci.net (Charles H. Ray, Jr.)]

>>Can these guys change sex?
>
>Too bad there was no comment on this. I'm pretty sure C. Punctulata still
>undergoes the only documented sex change for cichlids. I have heard a
>couple store employees mutter about taking the last male cichlid out of a
>tank and then finding another male a few weeks later. Sorry, I can't
>remember what species as I never really believed them enough to pay
>attention. Don't forget the C. Punctulata discovery was made by amateur
>aquarists though!
>
>-Doug Brown
>debrown@kodak.com
>

Some species may appear to change sex.  The first A. agassizi I had were
wild caught and bought as a male and 3 females.  All 4 were placed in a
heavily planted 10 gallon tank with lots of caves.  The male spawned
several times with one of the females and produced fry of which none
survived.  As luck would have it the male jumped out, this is several
months later.  I think I'm out of luck now, but lo and behold, within just
a few weeks, one of the "females" suddenly puts on a growth spurt and is a
male.  He spawns with one of the two females.  Again, fry are produced but
I don't manage to save any.  Some weeks or even months later, this now
large (2-1/2") male also dies on the carpet.  Lo and behold, another
"female" suddenly blossoms into a male and he was ultimately the largest
and most beautiful of the lot.  He also spawned with the female and
produced several large spawns that I successfully grew out and sold to
LFSs. Never would many of the fry develop definite male colors and finnage.
I never followed up to see if most were females or were the males either
masquerading as females or possibly being prevented from getting enough to
eat.  I know that the developed red agassizi's seem to produce adequate
numbers of obvious males, but this definitely was not the case with these
wild fish.  As an aside, the third male ultimately jumped out when he was
about 3 years old.

I have seen similar happening with A. viejita.  I also used to raise lots
of Nannacara anomala and the only way to get lots of large colorful males
from a batch was to pull out the dominant male (rarely 2) from the grow-out
tank and allow additional an additional male or males to grow large and
colorful.  Eventually I would end up with a tank of very nice males and a
tank of almost all females, but if I didn't remove the males most would
never grow out, at least in a group setting.  And I'm convinced some male
A. borellii never develop the color and long finnage and fit into the
definition of a sneaker male.  Due to the large numbers of N. anomala I was
growing out and the availability of food, I really believe the first male
to develop was hormonally suppressing the others in the tank.  I can't
prove it but if I start breeding them again in large numbers I may try to
prove it by seeing if male can suppress development in siblings in another
tank but sharing the same water.