Re: fishy information...

[Mike & Diane Wise <apistowise@fgn.net>]

Frank,

Just because a female-like fish takes on male
features and fertilizes eggs doesn't mean it is
hermaphroditic. It could be that the "female" was
actually an immature or sneaker male waiting its
chance to become the dominant male. The only way
to determine if a species is a hermaphrodite is to
do breeding experiments. First a female specimen
has to produce offspring in a tank containing only
1 male. No other specimens should be in the tanks
since this introduce uncertainties like who is the
actual breeding female. Once a specimen has proven
to be a reproductive female. She should then be
placed in a tank with another similarly tested
reproductively proven female. If one changes to a
male & the 2 fish produce viable offspring, then
hemaphroditism is proven for this male. If results
with multiple similar pairs are positive, then the
species can be considered hermaphroditic.

Ted Judy's example for D. filamentosus, that you
cite, does not meet the required criteria, so it
can't be considered absolutely positive. On the
other hand, he claims that the female in question
had red ventral fins. Red ventrals only appear in
females of this species once they have spawned, so
this indicates that the 'male' once was a breeding
female. Unfortunately we only have Ted's word for
it & he may have thought that all of the 'females'
had red ventrals when some did not - typical of
immature males & females of this species when
commercially collected. D. filamentosus is a
crenicarine, in which we know of only 1 other
crenicarine with indications of hemaphroditism,
Crenicara punctulatum. To my knowledge even C.
latrunculatum has never shown any hermaphroditic
tendencies. Dicrossus (other than Judy's report) &
Mazurunia have not been reported to be
hermaphrodites either. That tends to indicate that
hemaphroditism is unusual among the crenicarine.

Based on the data given, I doubt that D.
filamentosus is a hermaphroditic species, but
certainly cannot rule it out entirely. This would
make an excellent research project for someone
interested in keeping & breeding this beautiful
fish.

Mike Wise

"F. Tadeo" wrote:

> Doing research on the net on how to breed d.
> filamentosus, I stumbled upon this article that
> said that they were hermaphroditic.  This guy
> based his conclusion on his experience that
> after he lost his male, one of the "females"
> turned into a male. D. filamentosus is not
> hermaphroditic is it?  His "female" was probably
> a sleeper male right? Here is the link if anyone
> wants to see the article:
> http://www.petsforum.com/cichlidroom/articles/a091.html Thanks,Frank ps.
> Ram fry are doing great on bbs fed from day
> one!  I don't think I've lost more than 2 or 3
> babies so far.  Thanks again for everyone's
> suggestions.  Only problem now is that dad won't
> eat since he's so busy defending the fry and has
> started to fight off and reject mom, even though
> she vigorously defends the perimeter around the
> fry.  Go figure.
>
>
> -------------------------------------------------
> Chat with friends online, try MSN Messenger:
> Click Here
>
> ------------------------------------------------------------------------
> This is the apistogramma mailing list,
> apisto@listbox.com. For instructions on how to
> subscribe or unsubscribe or get help, email
> apisto-request@listbox.com.
> apisto-digest@listbox.com also available. Web
> archives at http://lists.thekrib.com/apisto
> Trading at
> http://blox.dropship.org/mailman/listinfo/apisto_trader


-------------------------------------------------------------------------
This is the apistogramma mailing list, apisto@listbox.com.
For instructions on how to subscribe or unsubscribe or get help,
email apisto-request@listbox.com. apisto-digest@listbox.com also available.
Web archives at http://lists.thekrib.com/apisto
Trading at http://blox.dropship.org/mailman/listinfo/apisto_trader