Chaetosalpinx Sibiriensis02 on:
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''Chaetosalpinx'' is an 
ichnogenus
An ichnotaxon (plural ichnotaxa) is "a taxon based on the fossilized work of an organism", i.e. the non-human equivalent of an artifact. ''Ichnotaxon'' comes from the Ancient Greek (''íchnos'') meaning "track" and English , itself derived from ...
of bioclaustration
Bioclaustration is kind of interaction when one organism (usually soft bodied) is embedded in a living substrate (i.e. skeleton of another organism); it means "biologically walled-up". In case of symbiosis
Symbiosis (Ancient Greek : living wi ...
s (a type of trace fossil
A trace fossil, also called an ichnofossil (; ), is a fossil record of biological activity by lifeforms, but not the preserved remains of the organism itself. Trace fossils contrast with body fossils, which are the fossilized remains of part ...
). ''Chaetosalpinx'' includes straight to sinuous cavities that are parallel to the host's axis of growth. The cavity is circular to oval in cross-section and it lacks a wall lining or floor-like tabulae. They are common in 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. ...
and rugose corals
The Rugosa or rugose corals are an extinct class of solitary and colonial corals that were abundant in Middle Ordovician to Late Permian seas.
Solitary rugosans (e.g., '' Caninia'', '' Lophophyllidium'', '' Neozaphrentis'', '' Streptelasma ...
from Late 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 ...
to 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 ...
of Europe and North America.
They may have been parasites.
References
{{Taxonbar, from=Q5066726 Trace fossils Silurian animals Devonian animals Late Devonian animals