I've recently been reading a lot of peoples comments throughout the forums trying to instruct others how to sex their geckos. I feel that a fair amount of these directions out there are either incomplete, or easily mis-construed, especially when they contain no visual reference.
Hopefully these photos will be of easy reference for new members to follow and understand.
First, a 45 gram male with an obvious bulge at the base of the tail. The bulge contains what is called the hemipenis ( side shot):
The same male with a shot from straight underneath the vent, also note in this photo the obvious pre-anal pores located on the undersides of the legs ( highlighted in the fifth photo posted here as well):
The hemipenal bulge in male crested geckos generally starts to become apparent between 10-15 grams, although there are exceptions, with some not showing an obvious bulge until after 15-20 grams.
Next up an adult female weighing in at 40 grams ( side shot). Please note, there is
no obvious bulge on a female crested:
And the same female from underneath:
As referenced in photo number two, the next photo is meant to show what are called the 'pre-anal' pores. These pores are a couple of rows of scales on the underside of the back legs on male crested geckos, that have little black spots on them. These are visible using a close up view ( scan, photo, loupe) of the underside of a male crested gecko that is around 5-10 grams, generally before a bulge is visible.
The pores you're looking for are lined up in the highlighted green box. This photo is of a 4.5 gram crested gecko male. Pre-anal pores will be absent on female crested geckos. Somtimes the pre-anal pores are difficult to locate on heavily patterned, or dark crested geckos.
Please note that these instructions are for R. ciliatus. While most of these tips/pointers follow through to all species of Rhacodactylus, some localities/morphotypes of leachianus are more difficult to sex. Also note that some female Rhacodactylus species have what are called pseudo-pores, which are scales that look like they have pores, but are not nearly as apparent as the pre-anal pores. These are generally very lightly dimpled rows of scales, that do not have an obvious darker pore located in the center. I'll try to make a follow up post in the R. auriculatus forum showing photos of pseudo pores in female gargoyle geckos, hopefully sometime in the near future.
Please let me know if there are any suggestions to help clarify this post, or if you have any questions.