Article · Wikipedia archive · Last revised Jul 17, 2026

Sphenothallus

Sphenothallus is a problematic extinct genus lately attributed to the conulariids. It was widespread in shallow marine environments during the Paleozoic.

Last revised
Jul 17, 2026
Read time
≈ 1 min
Length
269 w
Citations
6
Source
Wikipedia ↗
Sphenothallus
Temporal range:
Sphenothallus holdfast from the Kope Formation (Upper Ordovician), Gunpowder Creek, Kentucky.
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Cnidaria
Order: †Conulatae
Clade: †Conulariida
Genus: †Sphenothallus
Hall, 1847

Sphenothallus is a problematic extinct genus lately attributed to the conulariids. It was widespread in shallow marine environments during the Paleozoic.24

Occurrence

Sphenothallus is represented in the Cambrian period in the Kaili biota and the Mount Stephen trilobite beds, where it co-occurs with the similar organisms Cambrorhythium and Byronia.1 It is known in younger strata in Canada and the US, surviving at least until the Mississippian.3

Ecology

Sphenothallus lived in groups as an opportunist in environments from hardgrounds to soft mud, even if depleted in oxygen.3 It probably dispersed via larvae.3

Notes

Notes

  1. Earliest, upper Lower Cambrian (Van Iten et al 2002); latest, not referenced; at least to Mississippian
References

References

  1. Van Iten, H.; Zhu, M. Y.; Collins, D. (2002). "First Report of Sphenothallus Hall, 1847 in the Middle Cambrian". Journal of Paleontology. 76 (5): 902–905. doi:10.1666/0022-3360(2002)076<0902:FROSHI>2.0.CO;2. ISSN 0022-3360. JSTOR 1307202. S2CID 131018299.
  2. Bodenbender, B. E.; Wilson, M. A.; Palmer, T. J. (1989). "Paleoecology of Sphenothallus on an Upper Ordovician hardground". Lethaia. 22 (2): 217–225. Bibcode:1989Letha..22..217B. doi:10.1111/j.1502-3931.1989.tb01685.x.
  3. Neal, M. L.; Hannibal, J. T. (2000). "Paleoecologic and Taxonomic Implications Ofsphenothallusandsphenothallus-Like Specimens from Ohio and Areas Adjacent to Ohio". Journal of Paleontology. 74 (3): 369. doi:10.1666/0022-3360(2000)074<0369:PATIOS>2.0.CO;2. ISSN 0022-3360. S2CID 130829810.
  4. Vinn, O.; Kirsimäe, K. (2015). "Alleged cnidarian Sphenothallus in the Late Ordovician of Baltica, its mineral composition and microstructure". Acta Palaeontologica Polonica. 60: 1001–1008. doi:10.4202/app.00049.2013. Retrieved 2014-06-11.
External links