Tetragraptus approximatus Temporal range:
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Illustration of Tetragraptus approximatus | |
Original illustrations of Tetragraptus approximatus by Nicholson (1873). At the top is a magnified section of the stipes. A complete specimen is illustrated below. | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Hemichordata |
Class: | Pterobranchia |
Order: | †Graptoloidea |
Family: | †Dichograptidae |
Genus: | †Tetragraptus |
Species: | †T. approximatus
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Binomial name | |
†Tetragraptus approximatus Nicholson, 1873
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Tetragraptus approximatus is a species of dichograptid graptolite belonging to the genus Tetragraptus. It existed during the Floian Age (477.7 million years ago) of the Ordovician. It is an important index fossil in biostratigraphy.