Bubble Coral

Plerogyra sinuosa

''Plerogyra sinuosa'' is a species of "bubble coral". It has grape-sized bubbles which increase their surface area according to the amount of light available: they are larger during the day, but smaller during the night, when tentacles reach out to capture food. This species requires low light and a gentle water flow.
Branching Bubble Coral - Plerogyra sinuosa  Bubble Coral,Fall,Geotagged,Indonesia,Plerogyra sinuosa

Appearance

Colonies of ''Plerogyra sinuosa'' are in the form of an inverted cone that may be as much as a metre across. The corallites in small colonies are monocentric and trochoid, but become flabellomeandroiid in larger colonies. The septa have smooth margins but are irregularly arranged giving the colony an untidy appearance. The costae on young colonies sometimes form lobes which develop spines. These spines then elongate and a new polyp develops, this budding method being an unusual occurrence among corals.

In the living coral, ''Plerogyra sinuosa'' has vesicles resembling bubbles up to 2.5 cm in diameter. These enlarge during the day but retract to a certain extent during the night to expose the polyps and their tentacles.
Bubble Coral (Plerogyra sinuosa) Tanjung Paudean, Lembeh. Geotagged,Indonesia,Plerogyra sinuosa,Spring

Naming

Common names for ''Plerogyra sinuosa'' include "grape coral", "bladder coral", "pearl coral" and "branching bubble coral".
Acoela Flatworms on top of bubble anenome coral (Plerogyra sinuosa) Dauin, Oct 2012.
Acoels are very small flattened worms, usually under 2 millimetres (0.079 in) in length.
They are found worldwide in marine and brackish waters, usually having a benthic lifestyle, although some species are epibionts.
Members of the class Acoela lack a conventional gut, so that the mouth opens directly into the mesenchyme, i.e., the layer of tissue that fills the body. Digestion is accomplished by means of a syncytium that forms a vacuole around ingested food. There are no epithelial cells lining the digestive vacuole, but there is sometimes a short pharynx leading from the mouth to the vacuole. All other bilateral animals (apart from tapeworms) have a gut lined with epithelial cells. As a result, the acoels appear to be solid-bodied (a-coel, or no body cavity).

 Fall,Geotagged,Philippines,Plerogyra sinuosa,acoel flatworm,waminoa

Status

This is a common, widely-distributed species in shallow reef environments. It is subject to the threats of climate change and destruction of its reef habitat common to other coral species, and the International Union for Conservation of Nature has assessed its conservation status as being "near threatened".
Bubble Corals This Bubble Corals has Acoel (brown stuff) feeding on them. Bubble Coral,Corals,Mabul,Malaysia,Plerogyra sinuosa,Sabah

Behavior

''Plerogyra sinuosa'' is a zooxanthellate species of coral. It obtains most of its nutritional needs from the symbiotic dinoflagellates that live inside its soft tissues including the walls of the vesicles. These photosynthetic organisms provide the coral with organic carbon and nitrogen, sometimes providing up to 90% of their host's energy needs for metabolism and growth. Its remaining needs are met by the planktonic organisms caught by the polyps.

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Taxonomy
KingdomAnimalia
DivisionCnidaria
ClassAnthozoa
OrderScleractinia
FamilyCaryophylliidae
GenusPlerogyra
SpeciesP. sinuosa