Phoronopsis Explained

Phoronopsis is a genus of horseshoe worm in the family Phoronidae, in the phylum Phoronida. The members of the genus live in tubes at the bottom of the sea.

Characteristics

Like other phoronids, members of this genus are benthic filter feeders with a worm-like body encased in a loosely fitting chitinous 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 (feeding organ). This distinguishes it from the genus Phoronis. The gut is U-shaped, with the anus close to the mouth. The larval form, found in the zooplankton, is known as an "actinotroch".^{[1] [2]}

Distribution

The distribution is global.

Species

• Phoronopsis albomaculata Gilchrist, 1907
• Phoronopsis californica Hilton, 1930
• Phoronopsis harmeri Pixell, 1912^[3] (possible synonym^[4] Phoronopsis malakhovi Temereva, 2000^[5])

A 2018 phylogenetic analysis indicates that Phoronopsis is a monophyletic genus, while Phoronis is paraphyletic.^[6]

Notes and References

1. http://www.marinespecies.org/imis.php?module=ref&refid=61305 World Register of Marine Species: Phoronida
2. http://www.jiffynotes.com/a_study_guides/book_notes/grze_02/grze_02_00147.html Phoronida
3. http://www.marinespecies.org/aphia.php?p=taxdetails&id=128546 World Register of Marine Species
4. http://paleopolis.rediris.es/Phoronida/SYST/HARM/harmeri.htm Phoronopsis harmeri
5. Temereva. E.N.. New phoronid species Phoronopsis malakhovi (Lophophorata, Phoronida) from the south China Sea . Zoologicheskii Zhurnal . 2000. 79. 9. 1088–1093. Russian.
6. 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.