Ichnofossils

Tremichnus Brett, 1985

Taxon description

Buatois et al., 2017

2.63. Circular holes and pit-shaped borings

Wisshak et al., 2015

Emended diagnosis.Circular pits, generally wider than deep, perpendicularly bored into ossicles of echinoderms.

Knaust, 2012a

Unbranched, circular, bioerosional trace.

Brett, 1985

Circular pits or embedment structures of varying diameter (about 0.1 to 4.0 mm) occurring on the plates of echinoderms, primarily crinoids, with or with out associated thickening or gall-like deformation of the plates. Pits regularly parabolic in cross section, with diameter/depth ratios variable from about 0.1–1.0; no internal expansion or other ramifications. Holes always oriented perpendicularly to external plate surfaces, tapering in ward; generally not penetrating through plates. Adjacent pits
may over lap one an other.

Selection of related publications
Vinn, O., Wilson, M. A., Ausich, W., Toom, U. 2015. Tremichnus in crinoid pluricolumnals from the Silurian of western Estonia (Baltica). Carnets de Géologie 15, 17, 239-243. DOI:10.4267/2042/57951
Vinn, O., Wilson, M. A., Toom, U. 2015. Bioerosion of Inorganic Hard Substrates in the Ordovician of Estonia (Baltica). PLOS ONE 10, 7, e0134279. DOI:10.1371/journal.pone.0134279
Rozhnov, S. V. 1989. New data about rhipidocystids (Eocrinoidea). Fossil and Recent Echinoderm researches, pp. 38-57.
Franzén, C. 1974. Epizoans on Silurian-Devonian crinoids. Lethaia 7, 4, 287–301. DOI:10.1111/j.1502-3931.1974.tb00905.x