Article · Wikipedia archive · Last revised Jul 21, 2026

Arbacioida

Arbacioida are an order of sea urchins, consisting of a single extant family, the Arbaciidae. They are distinguished from other sea urchins by the presence of five separate plates around the anus. Unlike their close relatives, the Salenioida, all of the tubercles on their tests are of similar size.

Last revised
Jul 21, 2026
Read time
≈ 1 min
Length
154 w
Citations
Source
Arbacioida
Temporal range:
Arbacia lixula
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Echinodermata
Class: Echinoidea
Superorder: Echinacea
Order: Arbacioida
Gregory, 1900
Family: Arbaciidae
Gray, 1855

Arbacioida are an order of sea urchins, consisting of a single extant family, the Arbaciidae. They are distinguished from other sea urchins by the presence of five separate plates around the anus. Unlike their close relatives, the Salenioida, all of the tubercles on their tests are of similar size.

This order includes about 50 species (roughly 24 extant) divided into 14 genera:

References

References

  • Barnes, Robert D. (1982). Invertebrate Zoology. Philadelphia, PA: Holt-Saunders International. p. 980. ISBN 0-03-056747-5.
  • National History Museum. "Arbacioida". Retrieved 19 Dec 2009.