I live in Shimoda,Japan. I go diving and snorkeling on a weekly basis. This summer I have seen a coral that I have never seen here before. The size was about 70cm across.

What want to know is:

In what climate they usually grow?

Tropical? Sub tropical?

Looks like it may be an Acropora. Really need a close-up shot showing the ends of an arm. As well it looks like a fairly young colony (small size - few polyps) so may not have developed much of the 3-dimenional aspects of one that is more developed.