Genus

Discoceras Barrande, 1867

Taxon description

Kröger & Aubrechtová, 2019

Diagnosis (after Furnish & Glenister 1964). Gradually expanding conchs with a ribbed or smooth shell surface, characterized by a slight to moderate whorl overlap, circular to subquadrate whorl cross section, central position of siphuncle in initial half-volution, marginodorsal in succeeding 1.5–2 whorls, subdorsal at maturity, and thick, layered connecting rings.

Selection of related publications

Aubrechtová, M., Korn, D., Kröger, B. 2026. The genus Discoceras (Tarphyceratida, Cephalopoda; Ordovician) from Estonia and glacial erratics in north-central Europe. Journal of Taphonomy 1-54. DOI:10.5852/ejt.2026.1036.3173

Kröger, B. 2025. The Lyckholm acme of cephalopods – Review of the late Katian (Vormsi–Pirgu regional stages) Ordovician cephalopods of Estonia. European Journal of Taxonomy 978, 1-169. DOI:10.5852/ejt.2025.978.2801

Kröger, B., Aubrechtová, M. 2019. The cephalopods of the Kullsberg Limestone Formation, Upper Ordovician, central Sweden and the effects of reef diversification on cephalopod diversity. Journal of Systematic Palaeontology 17, 12, 961-995. DOI:10.1080/14772019.2018.1491899

Kröger, B., Aubrechtová, M. 2018. Cephalopods from reef limestone of the Vasalemma Formation, northern Estonia (latest Sandbian, Upper Ordovician) and the establishment of a local warm-water fauna. Journal of Systematic Palaeontology 16, 10, 799-839. DOI:10.1080/14772019.2017.1347212

Kröger, B. 2013. The cephalopods of the Boda Limestone, Late Ordovician, of Dalarna, Sweden. European Journal of Taxonomy 41, 41, 1-110. DOI:10.5852/ejt.2013.41

Kröger, B., Ebbestad, J. O. R., Högström, A. E. S., Frisk, Ǻ. M. 2011. Mass concentration of Hirnantian cephalopods from the Siljan District, Sweden; taxonomy, palaeoecology and palaeobiogeographic relationships. Fossil Record 14, 1, 35-53. DOI:10.1002/mmng.201000014

Sweet, W. C. 1988. The Conodonta: morphology, taxonomy, paleoecology, and evolutionary history of a long-extinct animal phylum. Oxford Monographs on Geology and Geophysics 10, 1-212.

Sweet, W. C. 1958. The Middle Ordovician of the Oslo Region, Norway: 10. Nautiloid Cephalopods. Norsk Geologisk Tidsskrift 38, 1, 1-178.

Stumbur, H. A. 1956. On the nautiloids of Kohila Subseries (Upper Ordovician of East Baltic). Tartu Riikliku Ülikooli Toimetised 42, 176-185.

Stumbur, H. 1955. Eesti NSV ülem-ordoviitsiumi nautiloiididest [Diplomitöö. Juhendaja: A. Rõõmusoks]. pp. 1-159.

Balashov, Z. G. 1953. Svernutye i polusvernutye nautiloidei ordovika Pribaltiki. Trudy Vsesoûznogo Naučno-Issledovatel'skogo Geologo-Razvedočnogo Instituta (VNIGRI) 217-300. Gostoptehizdat.

Teichert, C. 1930. Die Cephalopoden-Fauna der Lyckholm-Stufe des Ostbaltikums. Paläontologische Zeitschrift 12, 3/4, 264-312. DOI:10.1007/BF03044452

Eichwald, E. 1861. Paleontologiâ Rossii. Drevnij period. II. Fauna grauvakkovoj, gornoizvestkovoj i medistoslancevatoj formacij Rossii. pp. 1-521. R. Golike (former Ya. Ionsona).

Eichwald, E. 1860. Lethaea Rossica ou Paléontologie de la Russie. Premier volume. Ancienne Période en deux sections. pp. XIX+1–1657. E. Schweizerbart. DOI:10.5962/bhl.title.52391

Eichwald, E. von 1840. Geognostičeskie zamečaniâ o Litve, Volyni i Podolii. Gorny Zhurnal 3, 7, 1-59.

List of species

1. Discoceras amtjaernense Kröger et Aubrechtová, 2019 | Sandbian

2. Discoceras angulatum (Saemann, 1854) | Pirgu Stage

3. Discoceras antiquissimum (Eichwald, 1842) | Nabala Stage→Pirgu Stage

4. Discoceras arctuatum (Lossen, 1860) | Darriwilian

5. Discoceras bandonis Remelé, 1890 | Idavere Substage

6. Discoceras boreale Sweet, 1958 | Darriwilian→Sandbian

7. Discoceras costatum Rasmussen et Surlyk, 2012

8. Discoceras damesii (Schröder, 1891)

9. Discoceras danckelmanni (Remelé, 1880) | Jõhvi Substage→Keila Stage

10. Discoceras depressum Sweet, 1958 | Darriwilian

11. Discoceras fleischeri Sweet, 1958 | Upper Ordovician

12. Discoceras gubkovense (Balashov, 1953) | Idavere Substage

13. Discoceras ievense (Balashov, 1953) | Jõhvi Substage

14. Discoceras nilssoni Kröger et Aubrechtová, 2019 | Sandbian→Katian

15. Discoceras paopense Kröger, 2025 | Katian

16. Discoceras rarospira (Eichwald, 1840) | Haljala Stage→Nabala Stage

17. Discoceras roemeri Strand, 1934 | Vormsi Stage→Pirgu Stage

18. Discoceras saemanni (Hyatt, 1894) | Katian

19. Discoceras siljanense Kröger, Ebbestad, Högström et Frisk, 2011 | Hirnantian

20. Discoceras spongistriatum (Balashov, 1953) | Upper Ordovician

Classification

Organism group	Biota
Domain	Eukaryota
Kingdom	Animalia
Phylum	Mollusca
Class	Cephalopoda
Subclass	Tarphyceratia
Order	Tarphyceratida
Family	Discoceratidae
Genus	Curtoceras
	Discoceras
Species	amtjaernense
	angulatum
	angustum
	antiquissimum
	arctuatum
	aseriense
	bandonis
	boreale
	circulare
	costatum
	damesii
	danckelmanni
	depressum
	fleischeri
	gubkovense
	ievense
	nilssoni
	paopense
	rarospira
	roemeri
	saemanni
	siljanense
	spongistriatum
	vasalemmense
Genus	Schroederoceras