Is this a male or a female betta?

[hulkamaniac]

I rescued this betta from Petco along with a male I put in my 5 gallon. This one went in my 75g community. Once I got it home and started looking at it, I started to wonder about the sex of the fish. I won't say right now what the store had it labeled as b/c I don't want to bias anyone. The fins don't seem as flashy as most males, but they look much more ornate than most females. I apologize for the poor quality of the pics. I'm just figuring out how to use the digital camera and the fish just wouldn't sit still. You don't want to know how many pics I have of the spot it just left.

[fish_4_all]

I would guess female. Body shape and coloring just don't say male.

[HannahJ]

I would say that is almost definately a male. Female bettas have very short fins and usually very dull coloring, and those fins are a bit too long and too brightly red to be a female's. Also, it's common for the fish the big chain stores sell to be a little less ornate than you might see on the internet, just because they're likelier to go for the cheaper, less fancy stock. Females will also commonly display barring, either verticle or horizontal depending on their mood, and I'm not seeing any of that here. Also, keep in mind that there are short-finned varieties of male bettas, known as plakat bettas, which come from fighting stock rather than ornate stock. If you want a good litmus test on the gender, put a mirror up next to it. If it is crazy violent in attacking it, it's a male. Females (usually) have no where near the aggression of males.

Hope that helped!

[Alshain]

http://freshaquarium.about.com/od/fi...tatour01_5.htm

Picture of a red female betta.

[Menagerie]

I used to have the most beautiful red female betta. A true beauty. Her friend, a blue female was the meanest little fish I have owned (outside of cichilds)! You cannot tell by agression level alone the sex of a betta, nor by color.
Meanie (sorry about the poor quality of the pic)

Two other colorful females I used to own are below.

The wild type male bettas are called plakat/plakatthia and have shorter fins as seen here. I have found them to be more hardy than the fancy tailed bettas and used to have a cute little blue one (no pic ). Some interesting facts on betta genetics can be found here. Only males make bubble nests, but it could take a while for you to find out (and there has been at least one report of a proven breeding female making her own bubble nest--the pics were pretty cool).

[DepotFish]

You can't sex a betta by colour or length of fins. To tell if this is a female simply look at her vent area, where she poops, and see if there is a white dot. This will be her ovipositor. Females are also much more likely to show horizontal stripes when stressed, and only females will show vertical stripes. S/he looks just like my red roundtail female. But I'd bet its a male.

[hulkamaniac]

Hmm. Apparently Petco was correct to label her a female. I had never seen a female with such developed fins before.

[Menagerie]

I had never seen a female with such developed fins before.

And now you have! Treat her right and she may become your favorite community fish. The red split tailed female lived in a 50 gal community tank for over a year (the blue one lived in solitary).

[hulkamaniac]

I'm moving mine out of tank where someone (I suspect blackskirts) were picking on her. I plan on keeping her with 3-4 swordtails.

[RoK]

Looks like a female to me. The fins do look a little longer than most females though.
Was it being kept in a cup or in a tank with others?

It's a male. I'd bet money on it. Lok at the lenght and the location of the dorsal fin and the placment of the anual fin. The Males dorasl fin will be back farther on the back and longer or come to apoint. The anul fin is rounded at the start of the fin around the aunal area. Females will be more square. It looks like a dorment Male give it a month or so and it'll start looking like a male.