Rotadiscus

Rotadiscus
Temporal range: Early Cambrian – Middle Cambrian[1]
Fossil of Rotadiscus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Stem group: Ambulacraria
Clade: Cambroernida
Class: Eldonioidea
Family: Rotadiscidae
Genus: Rotadiscus
Sun & Hou, 1987
Type species
R. grandis
Sun & Hou, 1987
Synonyms[2]
  • Brzechowia Dzik, 1991

Rotadiscus is a genus of discoidal animal known from the Cambrian Chengjiang biota[3] and classified with the eldonioids.[2]

As with other eldonioids, it was originally thought to have been pelagic, but is now thought to be benthic.[4]

In addition to the type species R. grandis, two other Rotadiscus species have been proposed. The first is known only from one complete juvenile specimen and a few fragments, and was originally described as "Brzechowia sp." It remains without a formal species name, but has been transferred to Rotadiscus.[5] The species initially described as R. guizhouensis has since been reassigned to the genus Pararotadiscus.[2]

A 2023 cladistic analysis based on new fossils places Rotadiscus, along with other eldonioids, as stem-group ambulacrarians in the clade Cambroernida.[6]

References

  1. ^ Chen, Jun-yuan; Zhu, Mao-yan; Zhou, Gui-qing (1995). "The early Cambrian medusiform metazoan Eldonia from the Chengjiang Lagerstätte" (PDF). Acta Palaeontologica Polonica. 40 (3): 213–244.
  2. ^ a b c Schroeder, Natalie I.; Paterson, John R.; Brock, Glenn A. (2018). "Eldonioids with associated trace fossils from the lower Cambrian Emu Bay Shale Konservat-Lagerstätte of South Australia". Journal of Paleontology. 92 (1): 80–86. Bibcode:2018JPal...92...80S. doi:10.1017/jpa.2018.6. ISSN 0022-3360. S2CID 197586878.
  3. ^ Zhu, Mao-Yan; Zhao, Yuan-Long; Chen, Jun-Yuan (2002-03-01). "Revision of the Cambrian discoidal animals Stellostomites eumorphus and Pararotadiscus guizhouensis from South China". Geobios. 35 (2): 165–185. Bibcode:2002Geobi..35..165Z. doi:10.1016/S0016-6995(02)00025-6. ISSN 0016-6995.
  4. ^ Dzik, Jerzy; Zhao, Yuanlong; Zhu, Maoyan (1997). "Mode of life of the middle Cambrian eldonioid lophophorate Rotadiscus". Palaeontology. 40 (2): 385–396. Retrieved 28 December 2024.
  5. ^ Masiak, M.; Żylińska, A. (1994). "Burgess Shale-type fossils in Cambrian sandstones of the Holy Cross Mountains" (PDF). Acta Palaeontologica Polonica. 39 (4): 329–340. Retrieved 28 December 2024.
  6. ^ Li, Yujing; Dunn, Frances S.; Murdock, Duncan J.E.; Guo, Jin; Rahman, Imran A.; Cong, Peiyun (May 10, 2023). "Cambrian stem-group ambulacrarians and the nature of the ancestral deuterostome". Current Biology. 33 (12): 2359–2366.e2. Bibcode:2023CBio...33E2359L. doi:10.1016/j.cub.2023.04.048. PMID 37167976.