Nephasoma abyssorum abyssorum (Koren and Danielssen, 1875)

Arctic-boreal species

Nephasoma abyssorum abyssorum - close up of the introvert with hooks

Nephasoma abyssorum abyssorum: hooks

Synonymy
Phascolosoma abyssorum Koren and Danielssen, 1875
Golfingia abyssorum Wesenberg-Lund, 1955

Distinguishing characteristics
Two retractors.
Short but fully developed digitiform tentacles.
Unique, spirally arranged, medium sized (50-150 µm) dark hooks.

Size
Common trunk length: 10-30 mm

Color
Smooth, white, gray, yellow

Habitat
It inhabits sand and mud, often associated with corals or Cerianthus. Rare in hard substrata, inside burrows of Clione abyssorum and in the valves of Lima excavata

Feeding
Unknown

Life cycle
Unknown

Distribution
Common in the northeastern Atlantic and Arctic Oceans; rare in the southeastern and northwestern Atlantic, the northwestern Pacific and Mediteranean. From 500-5300 m.

References

• Cutler EB (1994) The Sipuncula. Their Systematics, Biology, and Evolution. 1-453
• Cutler EB, Cutler NJ (1986) Revision of the genus Nephasoma (Sipuncula: Golfingiidae). Proceedings of the Biological Society of Washington 99:547-573
• Fischer W (1895) Die Gephyreen des Naturhistorschen Museums zu Hamburg. Abhaltungen aus dem Gebiet der Naturwissenschaften (Hamburg) 13:1-24
• Fischer W (1929) Die Sipunculiden, Priapuliden und Echiuren der Arktis. 5
• Gibbs PE (1982) The synonymy of the Golfingia species assigned to the abyssorum-section (Sipuncula). Sarsia 67:119-122
• Gibbs PE (2001) Sipunculans. Key and Notes for the Identification of British Species, Synopses of the British Fauna (New Series). Crothers J.H.// Hayward P.J.
• Gibbs PE, Cutler EB (1987) A classification of phylum Sipuncula. Bulletin of the British Museum Natural History Zoology 52:43-58
• Kędra M, Murina GV (2007) The sipunculan fauna of Svalbard. Polar Research 26:37-47
• Kędra M, Shields MA (2010) On the deep-sea Nephasoma species in the Eastern North Atlantic - A taxonomic guide, Marine Biology Research, DOI:10.1080/17451001003660293
• Murina GV (1977) Marine worms of the Arctic and boreal waters of Europe. Identification books of the USSR fauna
• Murina GV, Sorensen J (2004) Marine Worms of the Phylum Sipuncula in Faroese waters. Fròðskaparrit 51:280-291
• Pancucci-Papadopoulou MA, Murina GV, Zenetos A (1999) The phylum Sipuncula in the Mediteranean Sea. 1-109
• Saiz-Salinas JI (2007) Sipunculans and echiurans from the deep sea Angola Basin. Journal of Natural History 41:2789-2800
• Shields MA, Kędra M (2009) A deep burrowing sipunculan of ecological and geochemical importance. Deep-Sea Research I 56, 2057-2064
• Théel H (1875) Etudes sur des Gephyreens inermes des ers de la Scandinavie, du Spitsberg et du Groenland. Kungliga Svenska Vetenskaps-Akademies Handlingar 3:1-30
• Théel H (1905) Northern and arctic invertebrates in the collection of the Swedish State Museum. I. Sipunculids. Kungliga Svenska Vetenskaps-Akademies Handlingar 3:1-30
• Wesenberg-Lund E (1933) The collections of Gephyreans in the Royal Museum of Natural History of Belgium. Bulletin du Institute Royal des Sciences Naturelles de Belgique 9:1-15