Wow I love those Cycadidaes, in a biology practicum I read that they are one of the oldest plants on earth, they belong to the carboniferous era, so they are about 250 million years old.
Some of them are venesous for animals, and I know that some others are commercial, since they are cultivated to sell their edible seeds, but it is really difficult to work with these plants because their pollination periods are too long, just like the pinaceae.

My professors tried to germinate several cicadicas and palms, but it has taken them years to get them to the size they are now.

Excellent photos.