I grow quite a few anthurium species from seed. In the wild the berries get eaten by birds. When the birds eat the soft berry, their bill/beak is coated in the sticky mucus from the fruit and they attempt to wipe it off on a branch or rock. Often, this results in the hard seed getting stuck on the side of a tree, and then you get a happy epiphyte.
When I get fresh seed, I typically squish the berry in my hand and remove the seed. This lessens the chance of the berry pulp rotting and creating fungus or mold problems. Place your seeds on damp epiphyte media (I used a mix of tree fern with a tiny bit of humus) and keep under high humidy and light. In a very short time you should have tons of seedlings to grow out. Also, they berries can be literally squished into cracks and pockets in your terrariums where they should sprout, this can create an awesome natural look since the plant grows in place from the beginning so you often get insane root growth.
You're pretty lucky! I'd love to find quality A. scandens seed here!
Oh yeah, they're ripe once they get nice and big and easily fall off in your hand. A. scandens is normally bright white or cream colored. In all honesty I've pulled berries of all sizes and levels of ripeness and still got tons of seedlings...
I'm not 100% sure if this is A. scandens or A. trinerve, but I am leaning toward the latter.
Anyway, both are closely related, so your seed (berries) should look similar to this when they are ready. Actually, you can see that some of the berries have fallen already. So if you want every last seed, you should follow the advice already given and try to see if the berries will come off easily.
Thanks guys. The "berries" on mine look a bit different to yours so i'll post up pics shortly just to confirm mine is fruiting.
How many seeds per fruit?
I've never seen this species offered for sale or even grown here in aus before untill i found a large plant growing at the local botanic gardens so i took a small piece (naughty naughty). It was just finishing flowering when i got it and since then the spathe has been swelling. One or 2 are starting to turn white, shouldnt be much longer then.