Also known as Branching Coral, Cylindrical Porous Coral, Finger Coral, Hump Coral, Jewelled Finger Coral, Pore Coral, Yellow Cylindrical Coral, Yellow Finger Coral.
Found in abundance on reef tops of lagoons and back reef margins. These pictures have their tentacles extended.
Colours vary from cream, yellow, green to blue.
They feed on plankton.
Length - 1m
Depth - 0-40m
Widespread Indo-West Pacific
Stony corals have hard stony skeletons, their polyps have six tentacles or are made up of multiples of six. These are usually nocturnal, however if the sky's are overcast, then many will feed during the day.
Generally the more robust corals life on exposed areas, while the smaller corals live in sheltered lagoons or deeper waters.
Stony corals are reef building corals and embedded in their flesh are thousands of minute single-celled marine plants called zooxanthellae which accounts for their colour.
These corals support a huge diversity of life, their main predator being the crown-of-thorns sea star. (edit) Ref: http://www.coralsoftheworld.org/species_factsheets/species_factsheet_summary/porites-cylindrica/