Sexing juvenile D. filamentosa

[Borked]

Is there a simple way of doing this?

All of the D. filamentosa I see at the LFSs are small and do not show any signs of sex (that I can tell).

One of the LFS that I work for placed 3 juvies in a 10gal shallow open top show tank. One showed male within days and the other two showed nothing. He was taken home by an employee and within days of his departure the other two showed male. I took the larger brighter of the last two. Now the last one is alone and the 3 males are in need of mates. They have quite a few juvies in stock but sexing is the issue.

thanks in advance,
-Kyle

 

[tjudy]

All Dicrossus juviniles look like females without red fins until they start to reach sexual maturity. The males will get long fins and blue irridescence in the fins, the females will get darker blocks and red in the ventral fins. Get a group of six juviniles and let them grow up together. You will get a male and female to show up.

 

[mk_ultra]

It can be tough. especially if there is a dominant male there. Males may stay females and females stay females untuil the alpha fish is removed. Then the next alpha fish may turn into a male. Strange fish that uses sex changes in order to keep the species thriving.

 

[tjudy]

I have witnessed the sequential hermaphroditism in D. filamentosus. That will work to your advantage if you buy six juviniles. THe largest and most dominant will become a male, and the next will become the breeding female.

 

[Jason]

Do they actually change sex or subdominant males are "in hiding" untill the dominant one is removed?
I once had this experience with an Apisto (bought as Macmasteri, but it may have been a different species): I was sure I had a male and three females, they never spawned though. Then, when the male died one of the "females" became a male, and after his death another female started displaying male colours.... Did they actually change sex, as I read it is possible with some fish, or they were all males and only one was allowed to display his masculinity?

 

[mk_ultra]

The articles I've read said they changed sex. A known female who has laid eggs has the ability tolater on fertilize eggs. Seeming seen more frequently with marine fish. If I can find the article I will link it.
I have never seen it happen. I have been looking for a male for a while. I have two females and maybe I'll get lucky.

 

[apistodave]

buy a bunch and just have fun--I think apistos can change sex I believe I saw this once but I wouldnt be absolutely sure of this as their habit of mimicing females to avoid punishment can sort of cloud the issue

 

[tjudy]

I have seen D. filamentosus change sex. I am pretty confident. The female laid eggs. I removed the male and added a smaller female. A few months later the original female was the male, and the second female laid eggs. I was able to reproduce this with different fish in different tanks as well.

It is also possible that there are sneaker males in the species. My experience, however, was well controlled.

 

[Jason]

How great those fish are!!!
As a result of this thread they became the newest addition to my "most wanted" list.
Jason

 

[mk_ultra]

I am the newest witness. A local LFS got a shipment in of about 15. Since the probably heard of my skill of killing all male fish- they were of course females. Bright Orangey pec fins and no lyretail in sight.
For the next 3 weeks i continues to pay them a visit hoping that someone would stand up and take charge.
To make a long story short I grabbed the guy with the brightest hints of blue in the fins and in the face. He is happily growing his lyretail in a tank with my 2 females!

What I noticed is- My two females where in a very large tank. No need for aggression or one to become a dominant fish. These 15 fish were placed in tight quarters in the LFS. I imagine this lack of space may speed up the sex-changing?

 

[tjudy]

That is possible, though the going theory is that males produce a pheromone that prevents another male from developing. In a large tank situation, one would expect more males to appear (more territories). Maybe there needs to be aggression to trigger the development of a male before the pheromones get released.

 

[jerseyjay]

mk_ultra,

Which store are we talking about ?. I'm from Clifton also.

 

[mk_ultra]

I can't remember the name of it. It's the nice but very expensive one on RT 46. Fish Encounter I think. One thing though. I picked up the one I saw turning into a mail. His tail fin was beat up a little but he was shaping up.
He has blossomed here at home. But He is a spade tail- D. Maculata perhaps?
Besides ethics, can they breed with the Filamentosus?

 

[Neil]

That is possible, though the going theory is that males produce a pheromone that prevents another male from developing. In a large tank situation, one would expect more males to appear (more territories). Maybe there needs to be aggression to trigger the development of a male before the pheromones get released.

Interesting supposition. It would kind of change the face of pairing certain species if it were correct.