please help me to identify this coral

[bichocr]

Thanks

 

[parrthed]

Looks like a deflated Amplexidiscus fenestrafer (giant cup) mushroom to me.

 

[Apercula]

I agree its most likely amplexidiscus, how large is it? Larger specimens have a fairly distinct band around the outer rim of the disk, but it takes a while for the band to form.
Amplexidiscus get very large, and are capable of eating fish especially clowns and perching fish like hawks, gobies, and blennies.

My amplexidiscus, the day I got it, mostly deflated, showing the band I mentioned.

At its largest, about 16inches in diameter.

 

[bichocr]

thanks for your anwsers.

maybe it is 4 inches. Look this another pic