''Scolymia lacera'', the fleshy disk coral, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

stony coral Scleractinia, also called stony corals or hard corals, are marine animals in the phylum Cnidaria that build themselves a hard skeleton. The individual animals are known as polyps and have a cylindrical body crowned by an oral disc in which a ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Mussidae Mussidae is a family of stony coral in the order Scleractinia. Following a taxonomic revision in 2012, the family is now restricted to species found in the Atlantic Ocean, with Pacific species transferred to the new family Lobophylliidae. Many ...

. It occurs on reefs in shallow waters in the

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, the

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, the

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Bermuda ) , anthem = "God Save the King" , song_type = National song , song = " Hail to Bermuda" , image_map = , map_caption = , image_map2 = , mapsize2 = , map_caption2 = , subdivision_type = Sovereign state , subdivision_name = , e ...

and southern

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Description

''Scolymia lacera'' is a coral with a single, solitary polyp and does not increase in size by budding as do

colonial Colonial or The Colonial may refer to: * Colonial, of, relating to, or characteristic of a colony or colony (biology) Architecture * American colonial architecture * French Colonial * Spanish Colonial architecture Automobiles * Colonial (1920 au ...

species of coral. It is a small species with a diameter of up to . The radially-running ridges in the stony cup which it secretes can be seen through the fleshy body of the polyp. Its colour is variable and is usually some shade of greenish-brown. ''Scolymia lacera'' is very similar in appearance to ''Scolimia cubensis'' which occupies much the same range. The differences are mostly in the layout of the septa, the miniature ridges in the

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an adje ...

calyces in which the polyps sit. ''S. lacera'' tends to occupy better lit positions while ''S. cubensis'' is in less well lit locations. Where the two come in contact, ''S. lacera'' is more aggressive.

Distribution and habitat

''Scolymia lacera'' is found in the

, the southern half of the

, the

and southern

. It grows on reefs, rocky outcrops and steep reef slopes at depths of between .

Biology

''Scolymia lacera'' contains single-celled

symbiotic Symbiosis (from Greek , , "living together", from , , "together", and , bíōsis, "living") is any type of a close and long-term biological interaction between two different biological organisms, be it mutualistic, commensalistic, or parasit ...

algae called

zooxanthellae Zooxanthellae is a colloquial term for single-celled dinoflagellates that are able to live in symbiosis with diverse marine invertebrates including demosponges, corals, jellyfish, and nudibranchs. Most known zooxanthellae are in the genus ''Sy ...

in its tissues. These are

photosynthetic Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities. Some of this chemical energy is stored in c ...

and use energy from the sun to produce organic compounds from which the coral also benefits. Much of its energy needs are supplied in this way but it also extends its ring of short ''tentacle''s to catch

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

, feeding mostly at night. ''Scolymia lacera'' is an aggressive coral that attacks neighbouring corals that might deprive it of light. It does this by extruding filaments several centimetres long from its

mesenteries In zoology, a mesentery is a membrane inside the body cavity of an animal. The term identifies different structures in different phyla: in vertebrates it is a double fold of the peritoneum enclosing the intestines; in other organisms it forms co ...

. When these come in contact with another coral they secrete

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. A ...

s that in the course of several hours digest its soft tissues. Smaller corals may be killed by this attack while larger individuals may have the part within reach stripped back to the skeleton.

Status

The

IUCN Red List of Threatened Species The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biologi ...

lists this species as being critically endangered. Some of the factors affecting corals are a rise in sea temperature and consequent

coral bleaching Coral bleaching is the process when corals become white due to various stressors, such as changes in temperature, light, or nutrients. Bleaching occurs when coral polyps expel the zooxanthellae (dinoflagellates that are commonly referred to as alg ...

, increased severity of storms,

ocean acidification Ocean acidification is the reduction in the pH value of the Earth’s ocean. Between 1751 and 2021, the average pH value of the ocean surface has decreased from approximately 8.25 to 8.14. The root cause of ocean acidification is carbon dioxid ...

, coral disease and various human impacts.

References

{{Taxonbar, from=Q3314153 Mussinae Taxa named by Peter Simon Pallas Corals described in 1766