How do you spot a apistogramma trifasciata “sneaker male”

[fart]

Hi
I have a group of young apistogramma trifasciata, its just over 20 that had survived (they are around 8 months old).

My question is how well do “sneaker males” manage to hide in a group of this size? And
how well do they manage to imitate females?


I am fully aware of the possibility of only one male in the group. But what make me thin there might be some “sneaker males” is that some of them are much smaller than the dominant male and those that I clearly see are females.



Dominant male.

Male or female?

Female

With regards
RHD

 

[gerald]

A "sneaker male" is a sexually mature male with female-like coloration that intrudes on a spawning pair and releases sperm on the eggs. This happens mainly with fish that spawn in open pits (like sunfishes and some cichlids) but would be mighty difficult to get away with in cave-spawning fish where the female guards the nest site from other females. So I doubt this happens much with Apistos. Anybody have more info on sneaker-male breeding in cave-spawning cichlids ?

I think what you're really referring to are juvenile and subordinate males that look like females because their testosterone production is suppressed by a dominant male in a confined space (aquarium). Not really the same as a sneaker male, although I can see why aquarists like to use that term. Yes, they can look "indeterminate" like your second photo for a LONG time, maybe up to a year old, depending on how much he's getting harassed.

 

[Mike Wise]

Sneaker males do occur in cave spawning species like apistos as well as open substrate spawning species. I once had a trio of A. cf. alacrina Rotpunct in which 2 of the fish showed bright yellow/deep black brooding colors when fry became freeswimming. Both of these fish would lead the fry around the tank side by side. I thought that this was really odd, but since Rotpuncts are really maternal I just thought that a 'spinster sister' was helping mom with the fry. The strange thing was that very few fry would survive the joint care. At the time I thought maybe the losses were due to the fry being confused by having to respond to 2 different fish in brood dress. Well, once the male died the 'not-the-mama' fish started growing and turned into a nice big male. I think gerald is right, that sneaker males have a method of slowing the development of external male features. One way to encourage development of these males to produce their masculine features is to remove obvious males from the group of young. This will allow the next dominant male to develop. By continually removing males, you will have 2 tanks of fish - one with males and the other with (mostly) females.

 

[fart]

Thanks for the answers gerald and Mike Wise.

 

[gerald]

Interesting story Mike. Any clues as to whether the yellow "helper male" might have fertilized some eggs, or do you think the Alpha male was the only father? I guess there's no real way to know, without DNA testing.

 

[Mike Wise]

I agree; no real way of knowing. The sneaker male always seemed to be above the breeding cave (large piece of bamboo) when the other 2 were breeding, so it is possible that he did add his genes to the spawn.