Gender ID Apistogramma cacatuoides

[Tool13x]

Can anyone tell me what the sex is for this fish. I suspect I have a sneaker male on my hands. I bought this fish which looked very female at the lfs. I am trying to build a harem for my male in one of my tanks. After being alone in a quarantine tank for the last couple of weeks it seems like its exhibiting more male characteristics every time i look at it. Thanks for the help.

 

[Colin_T]

It's definitely a male.

Males have a long pointed dorsal fin with lots of colour, females don't get the colour and have a short dorsal fin. The first 3 fin rays of the dorsal fin will be significantly longer in males.

The male's tail will be flat on the end with filaments on the top and bottom edge of it. Females don't have the filaments and a slightly curved/ rounded tail.

Males grow to double the size of females and have colour on their fins. If the fish has big colourful fins it is a male.

 

[Essjay]

I agree with Colin, definitely a male.

I too bought a pair of A cacatuoides only to discover they were both male. Much later I did acquire a pair which bred and 5 of the fry grew to adults (the tank sprung a leak, I had to move mum back to the main tank and the fry to the quarantine tank so I'm surprised 5 made it). I thought I had 2 males, 3 females but after giving away the two males, one of the 'females' decided to change colour and finnage.