Editing Trace fossil (section)

== Common ichnogenera ==
[[Image:Petroxestes pera Ordovician Ohio.jpg|thumb|''[[Petroxestes]]'' borings in a hardground from the Upper [[Ordovician]] of southern [[Ohio]]]]
[[Image:RusophycusOrdovician.jpg|thumb|right|''[[Rusophycus]]'' trace fossil from the [[Ordovician]] of southern [[Ohio]]. Scale bar is 10 mm.]]
[[Image:Skolithos.jpg|thumb|''[[Skolithos]]'' trace fossil. Scale bar is 10 mm.]]
[[Image:ThalassinoidesIsrael.JPG|thumb|''[[Thalassinoides]]'', burrows produced by crustaceans, from the Middle [[Jurassic]], [[Makhtesh]] Qatan, southern [[Israel]]]]
[[Image:Trypanites01.jpg|thumb|''[[Trypanites]]'' borings in an Upper [[Ordovician]] [[hardground]] from northern Kentucky. The borings are filled with diagenetic [[Dolomite (mineral)|dolomite]] (yellowish). The boring on the far right cuts through a shell in the matrix.]]
[[Image:Trace fossils in Uruguay.JPG|thumbnail|''Ophiomorpha'' and ''Thalassinoides'' trace fossils produced by crustaceans found at Camacho formation from the Late [[Miocene]] in [[Colonia Department]], [[Uruguay]]]]
*''[[Anoigmaichnus]]'' is a [[bioclaustration]]. It occurs in the Ordovician bryozoans. Apertures of ''Anoigmaichnus'' are elevated above their hosts' growth surfaces, forming short chimney-like structures.
* ''[[Arachnostega]]'' is the name given to the irregular, branching burrows in the sediment fill of shells. They are visible on the surface of steinkerns. Their traces are known from the [[Cambrian]] period onwards.<ref name='VinnWilsonZatonToom2014'>{{cite journal
 | title = The trace fossil Arachnostega in the Ordovician of Estonia (Baltica)
 | year = 2014
 | author = Vinn, O.
 | author2 = Wilson, M.A.
 | author3 = Zatoń, M.
 | author4= Toom, U.
 | journal = Palaeontologia Electronica
 | volume = 17.3.40A
 | pages = 1–9
 | url = http://palaeo-electronica.org/content/2014/960-arachnostega-in-the-ordovician
 | access-date = 2014-06-10}}</ref>
* ''[[Asteriacites]]'' is the name given to the five-rayed fossils found in rocks and they record the resting place of [[starfish]] on the sea floor. ''Asteriacites'' are found in European and American rocks, from the [[Ordovician]] period onwards, and are numerous in rocks from the [[Jurassic]] period of [[Germany]].
* ''[[Burrinjuckia]]'' is a bioclaustration. ''Burrinjuckia ''includes outgrowths of the [[brachiopod]]'s secondary shell with a hollow interior in the mantle cavity of a brachiopod. 
* ''[[Chondrites (genus)|Chondrites]]'' (not to be confused with stony meteorites of the same name) are small branching burrows of the same diameter, which superficially resemble the roots of a plant. The most likely candidate for having constructed these burrows is a [[nematode]] (roundworm). ''Chondrites'' are found in marine sediments from the [[Cambrian]] period of the [[Paleozoic]] onwards. They are especially common in sediments which were deposited in reduced-oxygen environments.
* ''[[Climactichnites]]'' is the name given to surface trails and burrows that consist of a series of chevron-shaped raised cross bars that are usually flanked on either side by a parallel ridge. They somewhat resemble tire tracks, and are larger (typically about {{convert|4|in|cm|order=flip|abbr=on|0|disp=or}} wide) than most of the other trace fossils made by [[invertebrates]]. The trails were produced on sandy tidal flats during [[Cambrian]] time. While the identity of the animal is still conjectural, it may have been a large [[slug]]-like animal – its trails produced as it crawled over and processed the wet sand to obtain food.<ref>{{cite journal|last=Getty|first=Patrick|author2=James Hagadorn |title=Palaeobiology of the ''Climactichnites'' trailmaker|journal=Palaeontology|year=2009|volume=52|issue=4|pages=758–778|doi=10.1111/j.1475-4983.2009.00875.x|bibcode=2009Palgy..52..753G |citeseerx=10.1.1.597.192|s2cid=129182104 }}</ref><ref>{{cite journal|last=Getty|first=Patrick|author2=James Hagadorn |title=Reinterpretation of ''Climactichnites'' Logan 1860 to Include Subsurface Burrows, and Erection of ''Musculopodus'' for Resting Traces of the Trailmaker|journal=Journal of Paleontology|year=2008|volume=82|issue=6|pages=1161–1172|doi=10.1666/08-004.1|bibcode=2008JPal...82.1161G |s2cid=129732925}}</ref>
* ''[[Cruziana]]'' are excavation trace marks made on the sea floor which have a two-lobed structure with a central groove. The lobes are covered with scratch marks made by the legs of the excavating organism, usually a [[trilobite]] or allied arthropod. ''Cruziana'' are most common in marine sediments formed during the [[Paleozoic]] era, particularly in rocks from the [[Cambrian]] and [[Ordovician]] periods. Over 30 ichnospecies of ''Cruziana'' have been identified. See also [[Isopodichnus]].
* ''[[Entobia]]'' is a boring produced by endolithic clionaid [[sponges]] consisting of galleries excavated in a carbonate substrate; often has swollen chambers with connecting canals.
* ''[[Gastrochaenolites]]'' are clavate (club-shaped) borings also produced in calcareous hard substrates, usually by [[bivalve]]s.
* ''[[Oikobesalon]]'' is an unbranched, elongate burrow with single-entrance and circular cross-section produced by terebellid polychaetes. They are covered with thin lining which has a transverse ornamentation in the form of fusiform annulation.
* ''[[Petroxestes]]'' is a shallow groove boring produced by mytilacean bivalves in carbonate hard substrates.
* ''[[Planolites]]'' is a small, 1-5mm (0.039–0.197 in), unlined and rarely branched, elongate burrow with fill that differs from the host rock, and is found throughout the [[Ediacaran]] and the [[Phanerozoic]].
* ''[[Protichnites]]'' consists of two rows of tracks and a linear depression between the two rows. The tracks are believed to have been made by the walking appendages of [[arthropod]]s. The linear depression is thought to be the result of a dragging tail. The structures bearing this name were typically made on the tidal flats of [[Paleozoic]] seas, but similar ones extend into the [[Cenozoic]].
* ''[[Rhizocorallium]]'' is a type of [[burrow]], the inclination of which is typically within 10° of the bedding planes of the sediment. These burrows can be very large, over a meter long in sediments that show good preservation, e.g. [[Jurassic]] rocks of the [[Yorkshire]] Coast (eastern [[United Kingdom]]), but the width is usually only up to {{convert|2|cm|in|frac=4}}, restricted by the size of the organisms producing it. It is thought that they represent fodinichnia as the animal (probably a [[nematode]]) scoured the [[sediment]] for food.
* ''[[Rogerella]]'' is a small pouch-shaped boring with a slit-like aperture currently produced by [[acrothoracica]]n [[barnacles]].
* ''[[Rusophycus]]'' are bilobed "resting traces" associated with trilobites and other arthropods such as horseshoe crabs.
* ''[[Skolithos]]'': One well-known occurrence of Cambrian trace fossils from this period is the famous '[[Pipe Rock]]' of northwest [[Scotland]]. The 'pipes' that give the rock its name are closely packed straight tubes- which were presumably made by some kind of [[worm]]-like organism. The name given to this type of tube or burrow is ''Skolithos'', which may be {{convert|30|cm|in|0|abbr=on}} in length and between {{convert|2|and|4|cm|in|frac=4|abbr=on}} in diameter. Such traces are known worldwide from sands and [[sandstone]]s deposited in shallow water environments, from the [[Cambrian]] period (542&ndash;488 [[annum|Ma]]) onwards.
* ''[[Thalassinoides]]'' are burrows which occur parallel to the bedding plane of the rock and are extremely abundant in rocks, worldwide, from the [[Jurassic]] period onwards. They are repeatedly branched, with a slight swelling present at the junctions of the tubes. The burrows are cylindrical and vary from {{convert|2|to|5|cm|in|frac=4|abbr=on}} in diameter. ''Thalassinoides'' sometimes contain scratch marks, droppings or the bodily remains of the [[crustacean]]s which made them.
* ''[[Teichichnus]]'' has a distinctive form produced by the stacking of thin 'tongues' of [[sediment]], atop one another. They are again believed to be fodinichnia, with the organism adopting the habit of retracing the same route through varying heights of the sediment, which would allow it to avoid going over the same area. These 'tongues' are often quite sinuous, reflecting perhaps a more nutrient-poor environment in which the feeding animals had to cover a greater area of sediment, in order to acquire sufficient nourishment.
* ''[[Tremichnus]]'' is an embedment structure (i.e. [[bioclaustration]]) formed by an organism that inhibited growth of the crinoid host stereom.
* ''[[Trypanites]]'' are elongated cylindrical [[bioerosion|boring]]s in calcareous substrates such as shells, carbonate [[hardground]]s, and [[limestones]]. Usually produced by worms of various types and [[sipunculids]].