Odaraia

Odaraia
Temporal range: Cambrian Stage 3–Middle Cambrian
Fossil
Life restoration in presumed upside down swimming position
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Order: †Hymenocarina
Family: †Odaraiidae
Simonetta & Delle Cave, 1975
Genus: †Odaraia
Walcott, 1912
Species:
†O. alata
Binomial name
†Odaraia alata
Walcott, 1912
Synonyms
  • Eurysaces pielus Simonetta and Delle Cave, 1975
Diagram

Odaraia is a genus of bivalved arthropod from the Middle Cambrian. Its fossils, which reach 15 centimetres (5.9 in) in length,[1] have been found in the Burgess Shale in British Columbia, Canada.

Odaraia bore a large pair of eyes at the front of its body,[1] and may have had two smaller eyes in between.[2] It had a tubular body with at least 45 pairs of biramous limbs, and its tail had three fins – two horizontal, one vertical – which were used to stabilise the animal as it swam on its back.[1] It has been suggested to have been an actively swimming filter feeder or predator, using its limbs to capture or sift food items from the water column, before using its appendages to transfer food to its mouth.[1][3]

Material from the Burgess Shale described in 2024 preserved specimens with hitherto-undetected mandibles, a mechanism for predation, as well as spinose endites on certain limbs, a possible mechanism for filter-feeding.[4]

217 specimens of Odaraia alata are known from the Greater Phyllopod Bed, where they comprise 0.41% of the community.[5]

It is currently classified as a member of Hymenocarina, a group containing many bivalved arthropods.[6]

  1. ^ a b c d D. E. G. Briggs (1981). "The arthropod Odaraia alata Walcott, Middle Cambrian, Burgess Shale, British Columbia". Philosophical Transactions of the Royal Society B: Biological Sciences. 291 (1056): 541–582. Bibcode:1981RSPTB.291..541B. doi:10.1098/rstb.1981.0007. JSTOR 2395403.
  2. ^ Graham E. Budd (2008). "Head structure in upper stem-group euarthropods". Palaeontology. 51 (3): 561–573. Bibcode:2008Palgy..51..561B. doi:10.1111/j.1475-4983.2008.00752.x. S2CID 85297530.
  3. ^ "Odaraia alata". The Burgess Shale. Royal Ontario Museum.
  4. ^ Izquierdo‐López, Alejandro; Caron, Jean‐Bernard (24 July 2024). Barrett, Spencer (ed.). "The Cambrian Odaraia alata and the colonization of nektonic suspension-feeding niches by early mandibulates". Proceedings of the Royal Society B. 291 (2027): 20240622. doi:10.1098/rspb.2024.0622. ISSN 1471-2954.
  5. ^ Jean-Bernard Caron & Donald A. Jackson (2006). "Taphonomy of the Greater Phyllopod Bed community, Burgess Shale". PALAIOS. 21 (5): 451–465. Bibcode:2006Palai..21..451C. doi:10.2110/palo.2003.P05-070R. S2CID 53646959.
  6. ^ Izquierdo‐López, Alejandro; Caron, Jean‐Bernard (November 2021). Zhang, Xi‐Guang (ed.). "A Burgess Shale mandibulate arthropod with a pygidium: a case of convergent evolution". Papers in Palaeontology. 7 (4): 1877–1894. doi:10.1002/spp2.1366. ISSN 2056-2799. S2CID 236284813.