Species

Tremichnus paraboloides Brett, 1985

Type specimen data

holotype: Buffalo Museum of Scienc ; BMS E23971; Niagara Gorge at Lewiston; , Pits in Icthyocrinus laevis Conrad

Reference:

Brett, C. E. 1985. Tremichnus: a new ichnogenus of circular-parabolic pits in fossil echinoderms. pp. 625-635.

Taxon description

Brett, 1985

Diagnosis: Pits, circular, regularly and smoothly parabolic in cross section; about as deep as wide (depth/diameter ratio: 0.9); ranging in size from 0.1-3.6 mm in diameter (X = 0.95 mm, SD = 0.65, N = 529 pits); up to 100 pits of varying size may occur on a single calyx. Pit apertures sharply demarcated, flush; never beveled or surrounded by a raised rim or gall-like outgrowth, pits rarely associated with vague swelling of the underlying stereom; pits frequently intersecting at borders.

Synonymy list

1985 Tremichnus paraboloides n. ichnosp. — Brett , pp. 627, fig. 1, 2

1985 Tremichnus minutus n. isp. — Brett , pp. 629, fig. 4, 5

1985 Tremichnus cysticus n. isp. — Brett , pp. 628, fig. 3, 4

1989 Balticapunctum inchoatus Rozhnov, isp. nov. — Rozhnov , pp. 53, fig. 2:1-2

2015 Tremichnus paraboloides Brett, 1985 — Wisshak et al. , pp. 449

2017 Oichnus paraboloides Bromley, 1981 — Donovan & Pickerill , pp. 828

2022 Tremichnus paraboloides — Thomka, Vinn & Toom , fig. 2

Selection of related publications

Thomka, J. R., Vinn, O., Toom, U. 2022. Site-selectivity of symbiotic (parasitic?) pits in crinoid column material from the middle Silurian (Wenlock: Sheinwoodian) of western Estonia. Ichnos 29, 2, 71-75. DOI:10.1080/10420940.2022.2047038

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.

Brett, C. E. 1985. Tremichnus: a new ichnogenus of circular-parabolic pits in fossil echinoderms. Journal of Paleontology 59, 3, 625-635.

Classification

Organism group	Biota
Ichnofossil group	Ichnofossils
	Bioerosional trace fossils
Family	Centrichnidae
Genus	Tremichnus
Species	cysticus
	excavatus
	minutus
	paraboloides
	puteolus

References based on distribution

Rozhnov, 1989 Babino quarry Leningrad district Volkhov Stage
Rozhnov, 1989 Putilovo quarry, Leningrad Oblast Volkhov Stage
Rozhnov, 1989 Putilovo quarry, Leningrad Oblast Dapingian
Brett, 1985 Ordovician
Brett, 1985 Niagara Gorge at Lewiston
Thomka et al., 2022 Sepise outcrop Wenlock