Tentaculites

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title: "Tentaculites" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["devonian-animals", "late-devonian-animals", "tentaculita", "early-ordovician-first-appearances", "late-devonian-genus-extinctions", "silurian-animals-of-north-america", "paleozoic-life-of-ontario", "paleozoic-life-of-alberta", "paleozoic-life-of-the-northwest-territories", "paleozoic-life-of-nova-scotia", "paleozoic-life-of-quebec", "paleozoic-life-of-yukon"] description: "Extinct genus of invertebrates" topic_path: "general/devonian-animals" source: "https://en.wikipedia.org/wiki/Tentaculites" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Extinct genus of invertebrates ::

| fossil_range = | image = TentaculitidDevonian.jpg | image_caption = Tentaculitids from the Devonian of Maryland. | taxon = Tentaculites | authority = von Schlotheim, 1820 | subdivision_ranks = Species | subdivision =

• T. bellulus Hall, 1876
• T. exaltatus Talent, 1963
• T. grandis Roemer, 1870
• T. oswegoensis F.B. Meek & A.H. Worthen, 1865

Tentaculites is an extinct genus of conical fossils of uncertain affinity, class Tentaculita, although it is not the only member of the class. It is known from Lower Ordovician to Upper Devonian deposits both as calcitic shells with a brachiopod-like microstructure and carbonaceous 'linings'. The "tentaculites" (i.e. tentaculita) are also referred to as the styliolinids.

Affinity

::figure[src="https://upload.wikimedia.org/wikipedia/commons/a/a2/Tentaculites_bellulus.jpg" caption="''[[Tentaculites bellulus]]'' from the Middle Devonian of Wisconsin."] ::

The taxonomic classification of tentaculitids is uncertain. Some grouped them with pteropods, but there is no modern support and only superficial similarity. They may also be related to other conical shells of uncertain affinity including cornulitids, Anticalyptraea, microconchids and trypanoporids.{{cite journal |author=Vinn, O. |title=Adaptive strategies in the evolution of encrusting tentaculitoid tubeworms |journal= Palaeogeography, Palaeoclimatology, Palaeoecology |year=2010 |volume=292 |issue=1–2 |pages=211–221 |url=https://www.researchgate.net/publication/222285765 |access-date = 2014-01-11 |doi=10.1016/j.palaeo.2010.03.046 |bibcode=2010PPP...292..211V Their shell microstructure has warranted their comparison with the brachiopods and phoronids,{{cite journal | doi = 10.1080/11035897.2012.669788 | title = Phenetic phylogenetics of tentaculitoids — extinct problematic calcareous tube-forming organisms | year = 2012 | author = Vinn, O. | author2 = Zatoń, M. | journal = GFF | volume = 134 | issue = 2 | pages = 145–156 | s2cid = 83591938 | url = https://www.researchgate.net/publication/234023270 | access-date = 2014-06-11}} and the possible Ediacaran lophophorate Namacalathus.

Morphology

::figure[src="https://upload.wikimedia.org/wikipedia/commons/5/51/Tentaculites_2.jpg" caption="Sketch of a ''Tentaculites ornatus'', Silurian."] ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/3/3a/Tentaculitid041011.jpg" caption="Tentaculitid from the New Creek Limestone ([[Lochkovian]], Early Devonian) of New Creek, [[West Virginia]]."] ::

Tentaculitids have ribbed, cone-shaped shells which range in length from 5 to 20 mm. Some species septate; their embryonic shell, which is retained, forms a small, sometimes spherical, chamber.

Ecology

Some species are inferred to have been planktonic.

References

References

1. (2007). "Paleopalynology".
2. (1978). "Tentaculites: Evidence for a Brachiopod Affinity?". Science.
3. Wood, G.D., Miller, M.A., and Bergstrom, S.M. 2004. Late Devonian (Frasnian) tentaculite organic remains in palynological preparations, Radom−Lublin region, Poland. Memoirs of the Association of Australian Palaeontologists 29: 253–258.
4. (2009). "Organic Remains of Tentaculitids: New Evidence from Upper Devonian of Poland". Acta Palaeontologica Polonica.
5. Ager, 1963, Principles of Palaeontology
6. 1. Zhuravlev, A.Y., Wood, R.A., and Penny, A.M. (2015). Ediacaran skeletal metazoan interpreted as a lophophorate. Proc. R. Soc. B 282, 20151860. Available at: http://rspb.royalsocietypublishing.org/lookup/doi/10.1098/rspb.2015.1860.
7. LARSSON K.. (1979). "Silurian tentaculitids from Gotland and Scania". Fossils and Strata.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::