Dorsal fin flash of M. altispinosa fry

[Roy Wadey]

I have some Mikrogeophagus altispinosa fry that are now about 6 weeks old. All the fry have a very dense black coloration to the front portion of their dorsal fin that is much more extensive than the dark coloration of the first three spines in the adults, covering at least the first six or seven rays and the membranes between. This black mark is bordered on the posterior edge by a bright gold coloration. As the fry move about the aquarium they constantly raise and lower their dorsal fin spines so that the gold marking appears to flash on and off like a lighthouse beacon. Is this coloration normal in M. altispinosa fry, or is this a mutation in my spawn? If it is normal, how long does it persist before the adult coloration is established?

 

[Cichlids1]

Roy,

Mine are the same way. It almost seems the dark markings stop developing and the rest of the fish grows around the marking. My latest batch is about 7 months old and the fish are a bit over an inch, the dark marking looks more like it belongs on them. Good luck with them.


Ken

 

[tjudy]

That flash signal is likely a schooling mechanism. It allows the group to stay together. That is the hypothesis anyway. There are several exmples of fish that are brightly or distinctly marked as juviniles that may fall into this hypothesis.