It would be nice to know where they are from

They are from Sri Lanka at 6-10 m depth.

The ones that shows a clear "labyrinth like" structures as Mussismilia. We have them in South Atlantic. Numbers 4, 7 and the last one im not sure.

1- Merulinidae - Favites sp. but it could be different genus. You need skeleton to confirm both genus and species.

2- Merulinidae - Favites (flexuosa?) but you need skeleton to confirm both genus and species.

3- Merulinidae - Platygyra sp.  but you need skeleton to confirm both genus and species.

4- Poritidae - Porites sp. but you need skeleton to confirm the species.

5- Merulinidae - Favites sp. but it could be different genus. You need skeleton to confirm both genus and species.

6- Merulinidae - Platygyra sp. (or Leptoria) but you need skeleton to confirm both genus and species.

7- It's a sponge... Xestospongia? I'm not a sponges specialist.

8- Merulinidae - Dipsastrea sp. but you need skeleton to confirm both genus and species.

9- Merulinidae - Another species of Platygyra (daedalea?) but you need skeleton to confirm both genus and species.

10- It's a soft coral... Lobophyton? (Sinularia?)

Merulinidae is not an easy group to identify underwater (like most scleractinian corals :-) people might say. It will be great if you could collect a large piece for taxonomic check, and subsample for molecular purpose. Keep me posted!

Thank you Gustavo

Thank you very much Stephane for your identifications and information. I will send you my coral species identification list with the photos.

1- Favites pentagona

2- Favites abdita

6- Leptoria sp.

As Stephane De Palmas already wrote, You need the skeleton, or macro-photos of the coral, a flash or a uw-light would be helpfull.

This site would also help You:

http://coral.aims.gov.au/info/search.jsp

Dear Ralph-Walter,

Thank you very much for your identifications as well as for the information and web link. 

Best regards,

Gayashan