''Heteropsammia'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of apozooxanthellate corals that belong to the family

Dendrophylliidae Dendrophylliidae is a family of stony corals. Most (but not all) members are azooxanthellate and thus have to capture food with their tentacles instead of relying on photosynthesis to produce their food. The World Register of Marine Species incl ...

Anatomy

These corals consist of free-living, single polyps, of a diameter of around 2.5 cm. They form a symbiotic relationship with a

sipunculid The Sipuncula or Sipunculida (common names sipunculid worms or peanut worms) is a class containing about 162 species of sea, marine Annelid, annelid worms, that have secondarily lost their segmentation. Sipuncula was once considered a phylum of ...

worm, ''

Aspidosiphon corallicola ''Aspidosiphon muelleri'' is a species of unsegmented benthic marine worm in the class Sipuncula, the peanut worms. This worm is found in the eastern Atlantic Ocean, the Mediterranean Sea and in various locations in the Indo-Pacific region at dep ...

''. The worm lives in a cavity situated on the under surface of the coral and it pulls the polip over sandy substrates. They also present a facultative symbiotic relationship with

zooxanthella Zooxanthellae (; zooxanthella) is a colloquial term for single-celled photosynthetic organisms that are able to live in symbiosis with diverse marine invertebrates including corals, jellyfish, demosponges, and nudibranchs. Most known zooxanthell ...

e of the ''

Symbiodinium ''Symbiodinium'' is a genus of dinoflagellates that encompasses the largest and most prevalent group of endosymbiotic dinoflagellates known and have photosymbiotic relationships with many species. These unicellular microalgae commonly reside in ...

'' genus, as this link has been observed at shallow waters (under 40 m), but not at greater depths (where the corals live without the algae). ''Heteropsammia'' corals can sometimes establish symbiotic relationships with other marine species, such as hermit crabs, that live in the cavity where the endosymbiotic Sipunculid worm is usually located.

Nutrition

''Heteropsammia'' corals (of the species ''

Heteropsammia cochlea ''Heteropsammia cochlea'', also known as walking dendro, is a species of small solitary coral in the family Dendrophylliidae that is native to the Indo-Pacific area. Description This small solitary free-living coral, not more than 2.5 cm a ...

'') have been observed ingesting

salp A salp (: salps, also known colloquially as “sea grape”) or salpa (: salpae or salpas) is a barrel-shaped, Plankton, planktonic tunicate in the family Salpidae. The salp moves by contracting its gelatinous body in order to pump water thro ...

s in Leuk Bay, Koh Tao,

Gulf of Thailand The Gulf of Thailand (), historically known as the Gulf of Siam (), is a shallow inlet adjacent to the southwestern South China Sea, bounded between the southwestern shores of the Indochinese Peninsula and the northern half of the Malay Peninsula. ...

, thanks to their large gape, as the salps were larger than the corals mouth opening.

Species

The following

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

are listed in the

World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive catalogue and list of names of marine organisms. Content The content of the registry is edited and maintained by scien ...

(WoRMS): * ''

'' Spengler, 1781 * ''

Heteropsammia eupsammides ''Heteropsammia'' is a genus of apozooxanthellate corals that belong to the family Dendrophylliidae. Anatomy These corals consist of free-living, single polyps, of a diameter of around 2.5 cm. They form a symbiotic relationship with a si ...

'' Gray, 1849 * ''

Heteropsammia moretonensis ''Heteropsammia'' is a genus of apozooxanthellate corals that belong to the family Dendrophylliidae. Anatomy These corals consist of free-living, single polyps, of a diameter of around 2.5 cm. They form a symbiotic relationship with a Sip ...

'' Wells, 1964

Notes and references

{{Authority control Dendrophylliidae Cnidarians of the Indian Ocean Cnidarians of the Pacific Ocean Cnidarian genera