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Heterandria formosa/ color changes



I have a tank of Heterandria formosa (Least Mosquito Fish) and I've made
some interesting observations (I think ;-) ).
My fish were all caught wild, some from So  Florida (on Rt 75 between Ft
Lauderdale and the Gulf Coast) and some from the panhandle , but
certainly much farther north than the Rt 75 group.
	 I've noticed some differences in the two groups. The northern group
has the ability to lose all of its coloration. I've seen the females
turn virtually completely gold. 

The males do something similar in that they lose their stripe but become
a solid grey coloration. The males will do this when challenging one
another for dominance. They lose all of their stripe and accentuate a
spot on their dorsal fin and display the spot to each other, spreading
their dorsal fin and swimming sideways at each other, this finally ends
when one male attacks and chases the other. The strange thing is I swear
that only the two males (which came from the north ) do this and/or have
the ability to do this . Some of the other males do not seem to be able
to lose their coloration, nor do they seem as aggressive. The color
changing males even attack females if in an aggressive "mood".

	Has anyone observed the above mentioned behavior. It occurred to me
that maybe only the dominant males will change color, but there is one
female that doesn't change color and it came from the south. Somewhere I
remember reading about a gold variant of H formosa. Is it possible that
there is several color morphs of H formosa? This would include a non
fading morph, a morph that has the ability to lose its coloration and a
morph with no pigmentation? I'd almost go as far as to say that the
morph with the ability to lose its coloration, exhibits a differant
behavioral pattern (more aggressive, more territorial) than the other.
Could this represent two races?

													Chris Darrow

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