Female Molly behaving like male

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rezende

Aquarium Advice Apprentice
Joined
Apr 26, 2013
Messages
34
Location
Germany
Hello guys,

My gf gave me an aquarium one month ago and she wanted to see some fry around. So, I got 3 black mollies (1M + 2F) and 3 guppies (1M + 2F). Fair enough!!
One month has passed, and no fry yet. Maybe it's too early, although females are still rejecting the males and don't look like pregnant.

Anyway, I have noticed days ago a very weird thing with one of our female black mollies: her fin is growing like a gonopodium!! :huh:

She is the biggest fish we have, and fat! For some time we even thought she was pregnant. So, by her size I would say at least that she is already adult.

First weeks she had a regular female fin. Then it started growing, getting thinner and longer. Nowadays she even move it around like males do.

Picture of my fat molly two weeks ago (after some zucchini, sorry :oops:):
pecera-54.jpg

Picture of her today:
pecera-72.jpg

Picture of her moving her fin around:
pecera-74.jpg

I'm skeptic that "she is male" because I could have noticed when she arrived, but is it a normal behavior for a female?
 
She does look like a he, doesn't she!? Hmmm. Were they quite young when you got them? I believe they all look female at first and then the males change. (I think I read that right?). Hope someone can jump in and correct me if I'm wrong!
 
She does look like a he, doesn't she!? Hmmm. Were they quite young when you got them? I believe they all look female at first and then the males change. (I think I read that right?). Hope someone can jump in and correct me if I'm wrong!

Hmmm, I don't know how old, but she was already around 4 cm when arrived, with the intense dark color of an adult. Our male molly were chasing both of them (and being rejected, poor guy).
Recently, she started facing him, I don't know if confronting or what. Sometimes, when the male is closer she closes all her fins (even the tail) but don't allow him to touch her.

First weeks she had the anal fin very open, like the other female, the suddenly changed the behavior. Still doesn't look exactly like a gonopodium, but not as female fin either... :confused:

Since I noticed it very recently, I'll keep an eye and see what happens next.
 
Do, and keep us posted. I'm interested too. :)
 
Looks like a male to me. I had a male molly I got from a pet shop and he looked just like a female even though he was nearly full grown. I think it was due to cold water at the pet shop.
 
I think that it might have always been a male. I heard that all the males developed later, and that they look like females until they mature.
 
I think that it might have always been a male. I heard that all the males developed later, and that they look like females until they mature.

I have read something like this before. I'll wait and see. For while, the male molly is still trying to breed with both (real female and this one). Also, this one haven't tried anything to the real female yet, afaik.

I'll keep watching, then update it when she/he decides. :popcorn:

Thank you all for your comments!!
 
Got the same thing going on. Two fry survived and I thought they were both female. Both have the triangular shaped anal fin. however the smaller, skinner fry is starting to show male tendencies. He/she keeps trying to cozy up to the other fry and my adult molly. The fry are 2 1/2 months old. After some research I found it can take up to 6 months for the males to develop gondophen (? spelling). Guess I am going to have a male whether I wanted one or not. Hopefully I won't have a tank full of fry. My only adult has eaten 3 birthings already. My local pet store said she would take any I wanted to get rid of and give me store credit. Same for snails.
 
Hello guys!

Just for record, I would like to post the actual picture + comparison just for future reference.
This molly was sold as a female. She looked grown already when she came home. She started getting so fat that for few weeks I thought she was pregnant.

Then, it happened that "her" anal fin started growing. So, one month after she arrived, there is no more doubt that she is actually ... male... and I would say he is maybe the healthiest and biggest molly I ever had! Much bigger than the other male (who was already clearly male when arrived here).

Check the one-month difference...
molly_evolution.jpg

HE does not try to mate with the other female yet... I don't know why. Maybe it takes so time... At least he isn't behaving aggressively anymore.

The other male (the original one) became a problem. I had to isolated him in a breeding tank, because he was harassing the remaining female to death!
I don't know yet for how long I'll keep him there. Last time I tried to give him a chance, he started hunting the female right away. :(

While isolated there, the "now-male" provokes him by showing all his fins.
 
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