I have read that the larger species take up to 18 months to reach adulthood. I noticed that my females laid their first non-fertile eggs between 18-24 months. My little ones are almost 2 years and they are almost as long as their parents, but not quiet as big (body-wise).

Hope this helps.
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Lisa

1.0.0 P.m. grandis (Linus)
3.3.0 P. standingi (Kona and her 5 babies)
R.I.P. Toby (7/5/06) I miss you...