''Phoronopsis'' 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 horseshoe worm in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Phoronidae Phoronids (taxonomic name Phoronida, sometimes called horseshoe worms) are a small phylum of marine animals that filter-feed with a lophophore (a "crown" of tentacles), and build upright tubes of chitin to support and protect their soft bodies. ...

, in the phylum

Phoronida Phoronids ( taxonomic name Phoronida, sometimes called horseshoe worms) are a small phylum of marine animals that filter-feed with a lophophore (a "crown" of tentacles), and build upright tubes of chitin to support and protect their soft bodies ...

. The members of the genus live in tubes at the bottom of the sea.

Characteristics

Like other phoronids, members of this genus are

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...

filter feeder Filter feeders are aquatic animals that acquire nutrients by feeding on organic matters, food particles or smaller organisms (bacteria, microalgae and zooplanktons) suspended in water, typically by having the water pass over or through a s ...

s with a worm-like body encased in a loosely fitting

chitin Chitin (carbon, C8hydrogen, H13oxygen, O5nitrogen, N)n ( ) is a long-chain polymer of N-Acetylglucosamine, ''N''-acetylglucosamine, an amide derivative of glucose. Chitin is the second most abundant polysaccharide in nature (behind only cell ...

ous tube. The tube is buried in the substrate, and the worm is anchored to the tube by an ampulla, the swollen part of its abdomen. The genus is characterised by the epidermis folding under itself at the collar beneath the

lophophore The lophophore () is a characteristic feeding organ possessed by four major groups of animals: the Brachiopoda, Bryozoa, Hyolitha, and Phoronida, which collectively constitute the protostome group Lophophorata.Phoronis ''Phoronis'' is one of the two genus, genera of the horseshoe worm family (Phoronidae), in the phylum (biology), phylum Phoronida. The body has two sections, each with its own coelom. There is a specialist feeding structure, the lophophore, whic ...

''. The gut is U-shaped, with the anus close to the mouth. The larval form, found in the

zooplankton Zooplankton are the heterotrophic component of the planktonic community (the " zoo-" prefix comes from ), having to consume other organisms to thrive. Plankton are aquatic organisms that are unable to swim effectively against currents. Consequent ...

, is known as an "actinotroch".

Distribution

The distribution is global.

Species

* '' Phoronopsis albomaculata'' Gilchrist, 1907 * '' Phoronopsis californica'' Hilton, 1930 * ''

Phoronopsis harmeri ''Phoronopsis harmeri'' is a species of marine horseshoe worm in the phylum Phoronida. It was first described by H.L.M. Pixell in 1912, and was found off of Vancouver Island. Ecology This species has been found around the world in coastal habit ...

'' Pixell, 1912 (possible synonym '' Phoronopsis malakhovi'' Temereva, 2000) A 2018 phylogenetic analysis indicates that ''Phoronopsis'' is a monophyletic genus, while ''

Phoronis ''Phoronis'' is one of the two genus, genera of the horseshoe worm family (Phoronidae), in the phylum (biology), phylum Phoronida. The body has two sections, each with its own coelom. There is a specialist feeding structure, the lophophore, whic ...

'' is

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

.Temereva, E. N.; Neklyudov, B. V. (2018). A New Phoronid Species, ''Phoronis savinkini'' sp. n., from the South China Sea and an Analysis of the Taxonomic Diversity of Phoronida. ''Biology Bulletin''. 45(7): 617-639.

References

{{Taxonbar, from=Q2342483 Phoronids Taxa named by John Dow Fisher Gilchrist