MN 5 (biostratigraphic zone)

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In biostratigraphy, MN 5 is one of the MN zones used to characterize the fossil mammal faunas of the Neogene of Europe. It is preceded by MN 4 and followed by MN 6 and is part of the Orleanian age of the middle Miocene. [1] MN 5 starts within magnetostratigraphic chron C5Cr, at 17.0 million years ago, and ends at the start of chron C5Bn.1r, at 15.0 million years ago, although some different correlations have been proposed. [2] The reference locality used to correlate faunas with this zone is Pontlevoy-Thenay in France; other localities include La Retama in Spain, Castelnau-d'Arbieu in France, and Sandelzhausen in Germany. [3]

In this zone, the muroid rodent Cricetodon first appears in western Europe, as do the poorly known Lartetomys and Mixocricetodon . [4] In the extinct rodent family Eomyidae, the genus Ligerimys last appears during MN 5, but Keramidomys and Eomyops appear as immigrants. [3] The last European marsupial, Amphiperatherium , last appears in France and Spain during MN 5, but persists into MN 6 in Germany. [4]

The primate Pliopithecus first appears during MN 5. The rhinoceroses Prosantorhinus , Plesiaceratherium , Hispanotherium , and Gaindatherium make their last appearance, but Ancylotherium and Hoploaceratherium first appear during MN 5. Chalicotherium , a member of the related extinct family Chalicotheriidae, also appears for the first time. Several artiodactyls, such as the pig Conohyus , the deer Heteroprox and Dicrocerus , and the musk deer Micromeryx first appear, and the pigs Bunolistriodon and Aureliachoerus and the ruminants Amphimoschus and Lagomeryx last appear in MN 5. Two artiodactyl genera, Triceromeryx and Pseudoeotragus , occur only during MN 5. The primitive artiodactyl Cainotherium last appears in France and Spain, but persists into MN 6 in Germany. [4]

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References

  1. Mein, 1999, table 2.1
  2. Steininger, 1999, pp. 1617
  3. 1 2 Mein, 1999, p. 28
  4. 1 2 3 Mein, 1999, p. 29

Literature cited