redearslider.com

I know it may be too early to guess the sex of my turtles-

But lately I've noticed that one turtle has a concave undershell (plastron I guess). I know those of box turtles and tortoises have the concave shape but do RES have the shape as well? This is the same turtle that started to flutter at another turtle, see http://www.redearslider.com/forum/viewtopic.php?t=3977&sid=369406f74552046ff9a1fccc6cc784e8.

From what I understand, using the concave method of sexing an RES isn't 100%. The best way to tell is to judge by the tail, and the front nails. According to your other post they are only three inches...Mine were closer to three and half inches before the first signs of gender started to emerge, and it wasn't definate until they grew a bit more.

My male RES has a very slight concave plastron (towards the cloaca), though his shell always had problems. Overall, I haven't encountered enough male RES to make sure.

Same here. The concave shape takes place towards the rear a little in front of the hind legs. Do you suppose this is proof then?

I have never been able to tell the sex of the turtle by the plastron since there are so many things that can influence the plastron shape (diet, genetics, etc.).

The most sure-fire way to tell the difference is by the tail & front claws. The tail of my female RES is *very* small (1" long) even though her shell is 11" long. Many males (who are much smaller than my RES) get a tail that is 1.5-2" long & the front claws are so long, you *think* you need to clip them (but don't clip them because they don't need clipping.....it's normal for the nails to be this long).

The concave plastron doesn't really apply to aquatics, though I do have one eastern painted (my preemie) who doesn't have a completely flat plastron.

For me, the most reliable way to tell the sex is the tail and position of the cloaca.

In addition to my male having really long nails and an abnormally large tail for his size, his personality is very different than the three girls in the tank. He eats less, hides more, and isn't friendly. At 4.5" he has JUST started to socialize and court my biggest girl (8"), and it was immediately obvious that he was a male!

The concave plastron is more for land turtles and doesn't apply to RES. You can't tell the sex by this.

I've mentioned that my male RES seems to have slight concave anal scutes. It looks very similar to the one posted by tritansmom. I still haven't came across any more male RES but I have seen some pics of male cooters with this trait, though I'm still learning about that species.