''Gersemia'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

soft coral Alcyonacea, or soft corals, are an order of corals. In addition to the fleshy soft corals, the order Alcyonacea now contains all species previously known as "gorgonian corals", that produce a more or less hard skeleton, though quite different f ...

s 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 ...

Nephtheidae Nephtheidae is a family of soft corals in the phylum Cnidaria. Members of this family are known as carnation corals, tree corals or colt soft corals. They are very attractive and show a wide range of rich and pastel colours including reds, pinks ...

. Species in this genus are found in cold temperate and polar seas at depths ranging from to over . The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

is '' Gersemia loricata''.

Characteristics

Colonies of ''Gersemia'' are arborescent, growing erectly with one main stem. The polyps are most numerous at the branch tips and are unable to retract into the calyces. The walls of the stalk and branches are stiffened with sclerites which are often brightly coloured. Corals in this genus do not contain

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 ...

, the microalgae

symbionts 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 ...

found in some other corals.The nephtheid soft coral genus ''Gersemia'' Marenzeller, 1878, with the description of a new species from the northeast Pacific and a review of two additional species (Octocorallia: Alcyonacea)
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Species

The World Register of Marine Species includes the following

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 ...

in the genus: *'' Gersemia antarctica'' (Kükenthal, 1902) *'' Gersemia carnea'' Verrill *'' Gersemia clavata'' (Danielssen, 1887) *'' Gersemia crassa'' (Danielssen, 1887) *'' Gersemia danielsseni'' (Studer, 1891) *'' Gersemia fruticosa'' Sars, 1860 *'' Gersemia hicksoni'' (Gravier, 1913) *'' Gersemia japonica'' (Kükenthal, 1906) *'' Gersemia juliepackardae'' Williams & Lundsten, 2009 *'' Gersemia lambi'' Williams, 2013 *'' Gersemia liltvedi'' (Verseveldt & Williams, 1988) *'' Gersemia loricata'' von Marenzeller, 1878 *'' Gersemia marenzelleri'' Kükenthal, 1906 *'' Gersemia mirabilis'' (Danielssen, 1887) *''

Gersemia rubiformis ''Gersemia rubiformis'', commonly known as the sea strawberry, is a species of soft coral in the family Nephtheidae. It is found in the northwest Atlantic and the northeast Pacific Oceans. Description ''Gersemia rubiformis'' is a colonial coral ...

'' (Ehrenberg, 1834) *'' Gersemia studeri'' Verrill *'' Gersemia uvaeformis'' (May, 1900)

References

Nephtheidae Octocorallia genera {{octocorallia-stub