The Ordovician (/ɔːrdəˈvɪʃi.ən, -doʊ-, -ˈvɪʃən/ or-də-VISH-ee-ən, -⁠doh-, -⁠VISH-ən) is a geologic period and system, the second of six periods of the...

Cap Late D O–S The Late Ordovician mass extinction (LOME), sometimes known as the end-Ordovician mass extinction or the Ordovician-Silurian extinction, is...

The Late Ordovician, also called the Upper Ordovician by geologists, is the third epoch of the Ordovician period. At this time, Western and Central Europe...

The Early Ordovician is the first epoch of the Ordovician period, corresponding to the Lower Ordovician series of the Ordovician system. It began after...

geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago (Mya), to the beginning of the Devonian...

appearing in the Ordovician include: Cyclopyge (Early to Late Ordovician) Selenopeltis (Early to Late Ordovician) Parabolina (Early Ordovician) Cheirurus (Middle...

subdivided into six geologic periods (from oldest to youngest): Cambrian Ordovician Silurian Devonian Carboniferous Permian Some geological timescales divide...

The Great Ordovician Biodiversification Event (GOBE), was an evolutionary radiation of animal life throughout the Ordovician period, 40 million years after...

Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordovician Period 485.4 Ma. Most of the continents lay in the southern hemisphere...

Sacabambaspis is an extinct genus of jawless fish that lived in the Ordovician period. Sacabambaspis lived in shallow waters on the continental margins...

Ice Age (EPIA), the Early Paleozoic Icehouse, the Late Ordovician glaciation, the end-Ordovician glaciation, or the Hirnantian glaciation, occurred during...

Southeastern United States. The age is from the Late Cambrian to the Early Ordovician. Predominantly, it is composed of carbonates, chiefly dolomite, with some...

K–Pg Tr–J P–Tr Cap Late D O–S The Cambrian–Ordovician extinction event, also known as the Cambrian-Ordovician boundary event, was an extinction event that...

the Mexican amber by García-Villafuerte (2018). Redescription of the Ordovician malacostracan Wuningia multisegmenlata is published by Lin (2018). A member...

The Ordovician meteor event was a dramatic increase in the rate at which L chondrite meteorites fell to Earth during the Middle Ordovician period, about...

(Ordovician) Chlamydosphaeridia (Ordovician) Comasphaeridium (Ordovician) Coronitesta (Ordovician) Coryphidium (Ordovician) Costatilobus (Ordovician)...

[citation needed] As such, it's not until the Ordovician that the first crown-group members arise. By the Ordovician period the gastropods were a varied group...

and extending southwest to Longford and south to Navan is a province of Ordovician and Silurian rocks, with similarities to the Southern Uplands province...

; Owen, A. W. (2002), Palaeobiogeography and Biodiversity Change: The Ordovician and Mesozoic–Cenozoic Radiations, Geological Society Special Publication...

malacology known as teuthology. Cephalopods became dominant during the Ordovician period, represented by primitive nautiloids. The class now contains two...

into the super-continent Gondwana. The Ordovician spans from 485 million to 444 million years ago. The Ordovician was a time in Earth's history in which...

Orthoceras is a genus of extinct nautiloid cephalopod restricted to Middle Ordovician-aged marine limestones of the Baltic States and Sweden. This genus is...

(Ordovician) Actinotrypidae (Carboniferous-Permian) Anolotichiidae (Ordovician) Botrylloporidae (Ordovician-Devonian) Ceramoporidae (Ordovician-Devonian)...

an extinct order of stromatoporoid sponges. They lived from the Early Ordovician (Floian stage) to the Late Devonian (Famennian stage), though a few putative...

coast Ordovician genus, in prior times it was employed as a general name given to all straight-shelled nautiloids that lived from the Ordovician to the...

Iapetus Ocean and Khanty Ocean. The Ordovician period started at a major extinction event called the Cambrian–Ordovician extinction event some time about...

in the Middle Ordovician period. If rocks of unknown age are found to have traces of E. pseudoplanus, they must have a mid-Ordovician age. Such index...

chondrichthyan and acanthodian traits. Dating back to the Middle and Late Ordovician Period, many isolated scales, made of dentine and bone, have a structure...

Four of these peaks were statistically significant: the Ashgillian (end-Ordovician), Late Permian, Norian (end-Triassic), and Maastrichtian (end-Cretaceous)...

short range in the Middle Ordovician period. If rocks of unknown age have traces of E. pseudoplanus, they have a mid-Ordovician age. Such index fossils...