NANFA-- Questions about Heterandria formosa.....
Fri, 20 Jun 2003 14:04:33 EDT

Hi guys & gals....

I've got a few questions about Heterandria formosa that I was hoping that
someone here might have answers for. I've done a lot of searching on the
web but have yet to find answers to these.......

Are female H. formosa able to store sperm like other Poeciliids for
continuous fertilization of eggs or do they require insemination for each
egg(s)? Considering their differing way of gestation of their eggs and
delivery mode I was curious if they differed in this aspect as well. I have
a group of 52 females from one local population who I have isolated in a
40 gallon tank away from any males. Females who were previously
pregnant who have delivered their young do not seem to be gestating
any more young after a period of about five weeks.

I found a reference through "Google" of a research paper on H. formosa
which exhibit a "pugfaced" appearance (as soon as I saw that I immediately
thought of some of my H. formosa from a tidal ditch in Blakely which that
term seemed to describe perfectly). Unfortunately to access the paper
through the particular server it was posted on you had to pay for a membership
to that server host. Does anyone on the list perhaps have a copy of this
paper or information relating to it?

Does anyone also know of any work ever done with hybridization of H. formosa
with other species of Poeciliids? In a very old aquarium book from the
1950's I
found a list of livebearers which had been successfully crossed but according
this list H. formosa had not been crossed with any other species (which, I
considering all the differences in physiology from other Poeciliids is not
all that
surprising......but, then again, this information is 50 years old too)

Finally, on the web auction site there is a guy in California
is selling what he calls "Gold Heterandria formosa". He says that they are a
breeding aquarium strain --- unfortunately the photograph that accompanies the
description is pretty fuzzy so you don't get a great idea of how the fish
looks. Has
anyone here ever seen these or purchased a pair from this guy? I'm tempted to
buy some of these but thought I'd pick a few brains here first. You can see
of his listings of this fish and the photo at:

I thank you for your time and any information you can provide.

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