Basket star

Basket star
Temporal range: 358.86–0 Ma Carboniferous to Present
Astroboa nuda basket star feeding at night in the Red Sea
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Echinodermata
Class: Ophiuroidea
Superorder: Euryophiurida
Order: Euryalida
Lamarck, 1816
Families
Synonyms
  • Euryalae Mortensen, 1927
  • Euryalina Müller & Troschel, 1840

The Euryalida, commonly known as basket stars is an order of echinoderms belonging to the class Ophiuroidea. They are a type of brittle star with either branching arms (called "basket stars") or long and curling arms (called "snake stars"). It contains three extant families, Asteronychidae, Euryalidae and Gorgonocephalidae.

Characteristics

Close-up of Astroboa nuda arm

Many of the species in this order have characteristic repeatedly branched arms (a shape known as "basket stars", which includes most Gorgonocephalidae and two species in the family Euryalidae), while the other species have very long and curling arms, and go rather by the name of "snake stars" (mostly abyssal species).

Many of them live in deep sea habitats or cold waters, though some basket stars can be seen at night in shallow tropical reefs. Most young basket stars live on a specific type of coral. In the wild, they may live up to 35 years. They weigh up to 5 kilograms (11 lb). Like other echinoderms, basket stars lack blood and achieve gas exchange via their water vascular system. The madreporite is on the oral surface. Digestive glands are confined to central disc.

The basket stars are the largest ophiuroids, with Gorgonocephalus stimpsoni measuring up to 70 cm in arm length with a disk diameter of 14 cm.

Systematics and phylogeny

The fossil record of this group is rather poor and only dates back to the Carboniferous. The phylogenetic tree per O'Hara et al. (2017) is as follows.

Euryalida
Basket stars

There are three extant families. One extinct family was described in 2025.:

References

  1. 1 2 "Euryalida". WoRMS. World Register of Marine Species. 2026. Retrieved 3 November 2026.
  2. ↑ "Euryalida". GBIF. Retrieved 3 November 2026.
  3. ↑ Sabine Stöhr. "Euryalida". marinespecies.org. Retrieved 3 November 2026.
  4. ↑ "Euryalina". Integrated Taxonomic Information System.
  5. ↑ Smith, A.B.; Paterson, G.L.J. (1995). "Ophiuroid phylogeny and higher taxonomy: Morphological, molecular and palaeontological perspectives". Zool. J. Linn. Soc. 114 (2): 213–243. doi:10.1006/zjls.1995.0024.
  6. ↑ Neves, Bárbara de Moura; Wareham Hayes, Vonda; Herder, Erin; Hedges, Kevin; Grant, Cindy; Archambault, Philippe (2020). "Cold-Water Soft Corals (Cnidaria: Nephtheidae) as Habitat for Juvenile Basket Stars (Echinodermata: Gorgonocephalidae)". Frontiers in Marine Science. 7. doi:10.3389/fmars.2020.547896. ISSN 2296-7745.
  7. ↑ R.C. Brusca, G.J. Brusca. Invertebrates. Sinauer Associates, 2 ed.(2003)
  8. ↑ Grzimek's Animal Life Encyclopedia. Vol. 1. Gale Cengage. 2003.
  9. ↑ Clarkson, E.; Clarkson, E.N.K. (1998). Invertebrate Palaeontology and Evolution (4 ed.). Wiley-Blackwell.
  10. ↑ O'Hara, Timothy D.; Stöhr, Sabine; Hugall, Andrew F.; Thuy, Ben; Martynov, Alexander (2018). "Morphological diagnoses of higher taxa in Ophiuroidea (Echinodermata) in support of a new classification". European Journal of Taxonomy (416). doi:10.5852/ejt.2018.416.