trifasciata sexing

[fishgeek]

any tips for sexing trifasciata

obviously mature dominat males are easy it is differeniating between femals(many f mine seem to have vey long pectoral and anal fin extensions) and young submissive males

any difference in tail shape, females more rounded?

tips greatly appreciated

andrew

 

[Mike Wise]

I don't think I have ever seen a sexually mature male A. trifasciata that didn't have at least some slightly extended dorsal fin lappets. How large are your fish?

 

[fishgeek]

some are full size some are only about 1.5cm in length

i can pick out the males with extended rays in the dorsal, is that what you mean by lappets?

i was quite surprised by the length of the pectoral fin extensions in some of what i think are females.. can they extend to the anal fin?

is there any real difference in tail shape between sexes?

 

[Mike Wise]

some are full size some are only about 1.5cm in length

i can pick out the males with extended rays in the dorsal, is that what you mean by lappets?

Yes, technically a lappet is a fleshy membrane that extends behind and often above the spine.

i was quite surprised by the length of the pectoral fin extensions in some of what i think are females.. can they extend to the anal fin?

Both sexes of A. trifasciata have pectoral fins of normal length. I think you wanted to write "ventral" or "pelvic" fin. In this case both sexes have longer ventral fins than the typical apisto. The female's ventral can extend back to the anal fin, but the male's are much longer, extending back to the caudal fin in some exceptional specimens.

is there any real difference in tail shape between sexes?

Not much, if any, in my opinion.

 

[fishgeek]

sorry yes , pectoral fins are the small rounded one's up on the side
ventral fins(i always think of them as arms) are what i meant

so really i just have to go on length of dorsal
what would be the earliest sizewise that i could be confident about that in your opinion

thanks for the help
andrew

 

[Mike Wise]

I imagine that at 8 months of age, even sneaker males will show indication of a serrated front dorsal, even if the lappets aren't starting to develop. Size isn't as important as age.