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Discoaster

Discoaster
Temporal range: Paleocene–PleistoceneMost abundant during Miocene
Discoaster surculus 01.jpg
Discoaster surculus, about 15 μm across
Scientific classification
Domain: Eukaryota
(unranked): Haptophyta
Class: Prymnesiophyceae
Order: Coccosphaerales
Family: Coccolithaceae
Genus: Discoaster
Tan Sin Hok, 1931

Discoaster is a genus of extinct star-shaped marine algae, with calcareous exoskeletons of between 5-40 μm across that are abundant as nanofossils in tropical deep-ocean deposits of Neogene age. Discoaster belongs to the haptophytes. About 100 species can be recognized.

The International Commission on Stratigraphy (ICS) has assigned the extinction of Discoaster brouweri as the defining biological marker for the start of the Calabrian Stage of the , 1.806 million years ago. ICS has assigned the extinction of Discoaster pentaradiatus and Discoaster surculus as the defining biological marker for the start of the Gelasian Stage, 2.588 million years ago, the earliest stage of the . ICS further assigned the extinction of Discoaster kugleri as biological marker for the start of the Tortonian Stage of the Miocene, 11.62 million years ago.

Some species in this genus include:


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Wikipedia

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