Re: NANFA-- Rivulus marmoratus

Scott Davis (
Mon, 3 May 2004 12:00:13 -0500

I had good luck with them in salty water. However don't add many black worms
to brackish water, those worms don't last long, but will fatally foul the

A good site dedicated to them, compiled by Bruce Turner, is:

TFH magazine, February 1998, ran an especially interesting article "Sex and
the Single Killifish" by Kathleen Cole and David Noakes. I'll bet their
article in Copeia 1997: 596-600 includes much the same information.

They contend, as a result of their study, that most marmoratus start out as
functional females. If they don't encounter a male with a certain period,
they also develop testes and can lay self fertilizing eggs.

In some populations males develop from the get-go. In other populations
functional hermaphrodites will lose their ovaries and become "secondary
males." There is a photo of a field caught male by Will Davis-in-that site
listed above. They also discuss hermaphroditism in several other (marine)

Several years ago Science Magazine ran a fascinating article on their

Google will also yeeld up a bunch of stuff. Also see that Turner site for a

That TFH issue is available from the Jim Forshey's Aquatic Book Store . When I can't find aquarium literature anywhere
else, I still have a pretty good chance of finding it there.

If that doesn't work for you, e-mail me off list and I'll unwrap a copy and
(later this week) try to scan that TFH article - for purely personal
research purposes of course. :)

All the best!
Scott Davis
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