its kind of hard to say what it is...reason being is because no breeding tube is showing....but just so you know for future ref...the male has a little needle looking tube and the female has a larger tube..you can really tell which is which..so if you only have one in your tank then you might never know because he/she wont get into the "mood"
The only way to be 100% sure is when breeding. Even just looking at extended papilla might be confusing. I have a male that looks like a female, with only the tiniest indication of a bump above his head. He and my other three largest are approaching "that age", so their papilla get extended quite frequently, but it took me a while to identify two of them.