Cornulitida is an extinct order of encrusting animals from class

Tentaculita Tentaculita is an extinct class of lophophorates ranging from the Early Ordovician to the Middle Jurassic. They were suspension feeders with a near worldwide distribution. For a more thorough discussion, see '' Tentaculites''. The presence of ...

, which were common around the globe in the

Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

oceans, and survived until the

Carboniferous The Carboniferous ( ) is a Geologic time scale, geologic period and System (stratigraphy), system of the Paleozoic era (geology), era that spans 60 million years, from the end of the Devonian Period Ma (million years ago) to the beginning of the ...

. Organisms that may be the oldest cornulitids have been found in

Cambrian The Cambrian ( ) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordov ...

sediments of Jordan. Cornulitids had shells, and were subject to predation by boring and other means from the Ordovician onwards. Many survived attacks by predators. Several cornulitids were endobiotic symbionts in the

stromatoporoid Stromatoporoidea is an extinct clade of sea sponges common in the fossil record from the Middle Ordovician to the Late Devonian.Stock, C.W. 2001, Stromatoporoidea, 1926–2000: ''Journal of Paleontology'', v. 75, p. 1079–1089. They can be cha ...

s and

tabulate Tabulata, commonly known as tabulate corals, is a class of extinct corals. They are almost always colonial, forming colonies of individual hexagonal cells known as corallites defined by a skeleton of calcite, similar in appearance to a honeycomb. ...

s. Their affinity is unknown; they have been placed in many phyla, and have been considered worms, corals, molluscs and more. They appear to be closely related to other taxa of uncertain affinity, including the

microconchid The order Microconchida is a group of small, spirally-coiled, encrusting fossil "worm" tubes from the class Tentaculita found from the Upper Ordovician to the Middle Jurassic (Bathonian) around the world. They have lamellar calcitic shells, u ...

s, trypanoporids and tentaculitids.

Gallery

Cornulitids and bryozoan Bellevue.jpg, alt=Cornulitids and bryozoan Bellevue, Cornulitids on a bryozoan; Bellevue Member, Grant Lake Formation, northern Kentucky Conchicolites.jpg, ''Conchicolites'' sp. overview of the rings with spines,

Lilla Karlsö Lilla Karlsö is a small Swedish island in the Baltic Sea, situated about off the west coast of Gotland and from Stora Karlsö; it is part of Eksta socken. During summer there are tour boats from Djupvik south of Klintehamn. Environment The ...

Sweden Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...

Septalites septatus.jpg, ''Septalites septatus'' from the Silurian of

Gotland Gotland (; ; ''Gutland'' in Gutnish), also historically spelled Gottland or Gothland (), is Sweden's largest island. It is also a Provinces of Sweden, province/Counties of Sweden, county (Swedish län), Municipalities of Sweden, municipality, a ...

Cornulites cellulosus.jpg, ''Cornulites cellulosus'' from Wenlock of Saaremaa, Estonia

References

{{Taxonbar, from=Q5171922 Tentaculita Middle Ordovician first appearances Pennsylvanian extinctions Prehistoric animal orders