Genus

Tremichnus Brett, 1985

Taxon description

Wisshak et al., 2019a

Macroboring; substrate calcareous; tracemaker invertebrate

Buatois et al., 2017

Category of architectural design: 2.63. Circular holes and pit-shaped borings.

Knaust, 2012a

Unbranched, circular, bioerosional trace.

Wisshak et al., 2015

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

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., 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

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

Rozhnov, S. V. 1989. New data about rhipidocystids (Eocrinoidea). Fossil and Recent Echinoderm researches, pp. 38-57. Academy of Sciences of the Estonian SSR Institute of Geology.

Franzén, C. 1974. Epizoans on Silurian-Devonian crinoids. Lethaia 7, 4, 287–301. DOI:10.1111/j.1502-3931.1974.tb00905.x

List of species

1. Tremichnus paraboloides Brett, 1985 | Volkhov Stage

Classification

Organism group	Biota
Ichnofossil group	Ichnofossils
	Bioerosional trace fossils
Family	Centrichnidae
Genus	Augoichnus
	Centrichnus
	Lacrimichnus
	Ophthalmichnus
	Solealites
	Solichnus
	Tremichnus
Species	cysticus
	excavatus
	minutus
	paraboloides
	puteolus

References based on distribution

Vinn et al., 2015 Sepise outcrop Jaagarahu Stage
Vinn et al., 2015c Hilliste Quarry Juuru Stage
Franzén, 1974 Klinteberg, Gotland
Franzén, 1974 Visby, Gotland
Franzén, 1974 Håftingsklint, Gotland
Franzén, 1974 Follingbo, Gotland