tentaculites

{{Automatic taxobox

| fossil_range = {{fossil range | Early Ordovician | Late Devonian | ref={{Cite book | last1 = Traverse | first1 = A. | chapter = What Paleopalynology Is and Is Not | title = Paleopalynology | series = Topics in Geobiology | volume = 28 | pages = 1–43 | year = 2007 | isbn = 978-1-4020-6684-9 | doi = 10.1007/978-1-4020-5610-9_1}} }}

| 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{{Cite journal | last1 = Towe | first1 = K. M. | title = Tentaculites: Evidence for a Brachiopod Affinity? | journal = Science | volume = 201 | issue = 4356 | pages = 626–628 | year = 1978 | pmid = 17794124 | doi = 10.1126/science.201.4356.626| bibcode = 1978Sci...201..626T | s2cid = 22806221 }} and carbonaceous 'linings'.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.{{Cite journal | last1 = Filipiak | first1 = P. | last2 = Jarzynka | first2 = A. | title = Organic Remains of Tentaculitids: New Evidence from Upper Devonian of Poland | journal = Acta Palaeontologica Polonica | volume = 54 | pages = 111–116 | year = 2009 | doi = 10.4202/app.2009.0111| doi-access = free }} The "tentaculites" (i.e. tentaculita) are also referred to as the styliolinids.

Affinity

File:Tentaculites bellulus.jpg 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.{{who||date=December 2015}}Ager, 1963, Principles of Palaeontology 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.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.

Morphology

File: Tentaculites 2.jpg

File:Tentaculitid041011.jpg, 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.{{cite journal|author=LARSSON K. |year=1979 |title=Silurian tentaculitids from Gotland and Scania|journal=Fossils and Strata |volume=11 |pages=180}}

tentaculites

Affinity

Morphology

Ecology

See also

References

Further reading