Mine have not spawned yet. The little male might be too young still - I've had him for 6 months and he was a tiny juvi when I got him.
I thought the twitching was more for pairing in the beginning, but now I think it's sort of ongoing fem dom thing.
When I first introduced the little one to the big female, she did all the twitching and the male was possibly too young to understand. After a few weeks, they both did the twitching and have been doing so regularly for the past 5 months. Though, like I said, she doesn't do it as often as he does these days.
Oh well the guy I bought them from said that the female is about 2.5 years old and the male is about 2 years old, do you think that they're both good age?