Baltoniodus is an extinct genus of conodonts.

Baltoniodus
Temporal range: Dapingian–Sandbian
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Conodonta
Family: Balognathidae
Genus: Baltoniodus
Lindström, 1971[1]
Species
  • Baltoniodus alobatus
  • Baltoniodus cooperi
  • Baltoniodus gerdae
  • Baltoniodus medius
  • Baltoniodus navis
  • Baltoniodus norrlandicus
  • Baltoniodus prevariabilis
  • Baltoniodus triangularis
  • Baltoniodus variabilis

Use in stratigraphy

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The base of the Dapingian, the first stage of the Middle Ordovician, is defined as the first appearance of Baltoniodus triangularis.[2]

The Whiterock Stage refers mainly to the early Middle Ordovician in North America, it is often used in the older literature in a global sense. The Whiterock Stage is given a range from 471.8 (ca. 472) to 462 m.y.a., spanning close to 10 million years. Officially its start is defined by the potentially lowest occurrence of the conodont Protoprioniodus aranda or Baltoniodus triangularis.

B. gerdae has been found in the early Sandbian Bromide Formation, in Oklahoma, USA.

References

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  1. ^ Vom Anfang, Hochstand und Ende eines Epikontinentalmeeres. Maurits Lindström, Geologische Rundschau, March 1971, Volume 60, Issue 2, pages 419-438, doi:10.1007/BF02000464
  2. ^ David A. T. Harper; Tõnu Meidla; Thomas Servais (May 10, 2023). "A short history of the Ordovician System: from overlapping unit stratotypes to global stratotype sections and points". Geological Society, London, Special Publications. 532 (1). The Geological Society of London: 13–30. Bibcode:2023GSLSP.532..285H. doi:10.1144/SP532-2022-285. Archived from the original on 2024-05-18.
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