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Estonian Journal of Earth Sciences
ISSN 1736-7557 (Electronic)
ISSN 1736-4728 (Print)
Impact Factor (2022): 1.1
Short communication
A diverse Hirnantian scolecodont assemblage from northern Estonia and resilience of polychaetes to the end-Ordovician mass extinction; pp. 46–49

Olle Hints, Petra Tonarová

We report the discovery of a rich assemblage of latest Katian and Hirnantian scolecodonts (polychaete jaws) from a new Ordovician–Silurian boundary outcrop in the Reinu quarry, northern Estonia. The recovered polychaete fauna contains at least 40 species attributed to 11 families. Many common taxa appear to range from the latest Katian to the Hirnantian and into the Rhuddanian, indicating the resilience of jawed polychaetes to the end-Ordovician mass extinction. The Reinu assemblage is similar to the coeval faunas known from other Baltic sections, as well as from Anticosti Island, Canada, although with some specific features. The study revealed the highest abundance of scolecodonts in the Ordovician of Baltica, with ca 5400 maxillae per kilogram of rock recorded in the Siuge Member of the Ärina Formation, Porkuni Regional Stage, early Hirnantian.


Eriksson, M. 1997. Lower Silurian polychaetaspid polychaetes from Gotland, Sweden. GFF119, 213–230.

Eriksson, M. 2001. Silurian Ramphoprionid polychaetes from Gotland, Sweden. Journal of Paleontology75, 993–1015.<0993:SRPFGS>2.0.CO;2

Eriksson, M. E., Hints, O., Paxton, H. and Tonarová, P. 2013. Ordovician and Silurian polychaete diversity and biogeography. Geological Society, London, Memoirs38(1), 265–272.

Gul, B., Ainsaar, L. and Meidla, T. 2021. Latest Ordovician–early Silurian palaeoenvironmental changes and palaeotemperature trends indicated by stable carbon and oxygen isotopes from north­ern Estonia. Estonian Journal of Earth Sciences70(4), 196–209.

Harper, D. A. T., Cascales-Miñana, B. and Servais, T. 2020. Early Palaeozoic diversifications and extinctions in the marine biosphere: a continuum of change. Geological Magazine157(1), 5–21.

Hints, L., Hints, O., Kaljo, D., Kiipli, T., Männik, P., Nõlvak, J. et al. 2010. Hirnantian (Latest Ordovician) bio- and chemostratigraphy off the Stirnas-18 core, western Latvia. Estonian Journal of Earth Sciences59(1), 1–24.

Hints, O. 2000. Ordovician eunicid polychaetes of Estonia and surrounding areas: review of their distribution and diversification. Review of Palaeobotany and Palynology113, 41–55.

Hints, O. 2001. Distribution of scolecodonts. In Valga (10) Drill Core (Põldvere, A., ed.). Geological Survey of Estonia, Tallinn, 12–14.

Hints, O. and Eriksson, M. E. 2007. Diversification and biogeography of scolecodont-bearing polychaetes in the Ordovician. Palaeogeography, Palaeoclimatology, Palaeoecology245(1–2), 95–114.

Hints, O. and Eriksson, M. E. 2010. Ordovician polychaeturid polychaetes: Taxonomy, distribution and palaeoecology. Acta Palaeontologica Polonica55, 309–320.

Hints, O., Paris, F. and Al-Hajri, S. 2015. Late Ordovician scolcodonts from the Qusaiba-1 core hole, central Saudi Arabia, and their paleogeographical affinities. Review of Palaeobotany and Palynology212, 85–96.

Hints, O., Tonarová, P. and Desrochers, A. 2016. Late Ordovician jaw-bearing polychaetes from Anticosti Island, Eastern Canada, and their biogeographic significance. Canadian Journal of Earth Sciences53(7), 731–738.

Meidla, T., Ainsaar, L., Hints, O. and Radzevičius, S. 2023. Ordovician of the eastern Baltic Palaeobasin and the Tornquist Sea Margin of Baltica. Geological Society, London, Special Publications532, SP532-2022-141.

Tonarová, P., Vodrážková, S., Hints, O., Nõlvak, J., Kubajko, M. and Čáp, P. 2023. Latest Ordovician jawed polychaetes, chitinozoans and depositional environments of the Levín section, Prague Basin, Czech Republic. Geobios

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