A few weeks ago my friend and I bought a male and female Holothele incei to breed so we both can get a communal out of the deal. Well it turns out the male is mature (already put it in the breeding loan thread. Please let me know if anybody is interested. You can Whatsapp me, my cell is 0799308975). The female doesn't seem to be mature, as she is smaller then the male, the male has a DLS of 6 cm and the female 5 cm, as I read that when mature the female is much bigger then the male.

I would like to confirm my suspicion, comments are welcome.

Mature male ventral picture



This is the female, does it look mature?







This is a picture of both together, you can't see the size very well but the male is larger.

The easiest way to tell is to leave the male in with it and if it responds to his drumming and mates then you know it is mature. If it doesn't respond then it is either not ready, coming up for a moult or if you are unlucky it is a sub adult male.

The hooks are clearly visible on the male. I'm afraid if I leave it with the female it will die before any mating takes place. They have been in the same enclosure for a month so am I right in saying that if any mating will take place it would of already happened?

Probably.
When I was talking about sub adult males I meant your female.

Oh... I see. Hopefully that's not the case.

SIM-slayer wrote: The hooks are clearly visible on the male. I'm afraid if I leave it with the female it will die before any mating takes place. They have been in the same enclosure for a month so am I right in saying that if any mating will take place it would of already happened?

If they have been in the same enclosure for a month they would have all ready mated. There would of been no further mating, so you can remove the male for safe keeping.
For confirmation, if it is indeed a female, the waiting game starts for an egg sack to be made, make sure the substrate is nice and deep as they burrow under the substrate and make a chamber where they make the egg sack and care for it.

Question?
Did you maybe take pictures of your spiders when you got them? (The female more than the male.)
What has/is the female doing in the enclosure?

With regards to size of the spiders, Female H.incei's don't have to be full leg span to be able to give you an egg sack, they can be smaller as well.
With regards to males, I have the smallest MM I have ever seen and then I had a fairly large MM that disappeared in a maze of webs in the communal set-up, he was the same size as my largest H.incei female.