Single platy had a baby?

I have a 50 gallon aquarium that has one kissing gurami, one angelfish, 4 zebra danios, 4 Cory Cats, 2 sword tails, a green lantern platy and her baby. Yes this tank is over stocked but this was all given to me by a friend moving and in my apartment I can’t upgrade, there is no room! When I move in the summer I am upgrading.

This is not the point of my story however. I have owned these fish since September. Then my Platy became fat. A few weeks later I saw a fry which has been thriving since, I just assumed it was a Zebra Danio fry. It’s not! It has grown a lot and it’s a platy!! How? My green lantern platy is the only platy, so I called the original owner and she said she has never owned another platy. What happened? I don’t understand this. Can someone explain!

 

I don't have a ton of experience with livebearers. But I've heard that guppies can be born pregnant. Maybe it's the same for platies?

 

I may be wrong, but I think swordtails can breed with platies.

 

I don't have a ton of experience with livebearers. But I've heard that guppies can be born pregnant. Maybe it's the same for platies?

Wow! Maybe this is true for her!

I may be wrong, but I think swordtails can breed with platies.

I’m going to resource this, that would be interesting. I wonder what this baby will fully look like when she is mature!

 

How long did your friend have the platy? They will hold sperm for as long as a year, longer if conditions are not right for raising a batch of young. However, it is also true that domestic Swords and Platies are very much hybridized, and are still very close genetically, and such crosses are known to occur. Should be interesting to watch that fry growing up!

 

How long did your friend have the platy? They will hold sperm for as long as a year, longer if conditions are not right for raising a batch of young. However, it is also true that domestic Swords and Platies are very much hybridized, and are still very close genetically, and such crosses are known to occur. Should be interesting to watch that fry growing up!

I just asked, she had bought the platy in July, so two months before I got her.

 

She was impregnated already then, and was just waiting for the right environment to develop fry. Once fertilized by a male, a female can carry spermatophores for many months, and can have several broods of young from that one mating.

 

My platy had fry 6 months following purchase.

 

She was impregnated already then, and was just waiting for the right environment to develop fry. Once fertilized by a male, a female can carry spermatophores for many months, and can have several broods of young from that one mating.

Wow, I had no idea! I’m glad she feels safe enough to give birth.

My platy had fry 6 months following purchase.

That must be what’s happened to my platy.

 

Maybe the platy was fertilized at the pet store?

I read about platys a bit and it says the get pregnant very easily and are live bearers. Maybe your fish became pregnant at the pet shop? The article says that if a male and female are in the same tank they will probably breed.
Hope this helps a bit.