Shecenia

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Shecenia
Temporal range: Late Paleocene-Early Eocene
~57–54  Ma
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Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Astrapotheria
Genus: Shecenia
Simpson 1935
Type species
Shecenia ctirneru
Simpson, 1935
Species
  • S. ctirneruSimpson 1935

Shecenia is an extinct genus of mammal, probably belonging to the order Astrapotheria. It lived between the Late Paleocene and the Early Eocene, and its fossilized remains were found in South America.

Description

This animal is known from very fragmentary remains, including a partial mandible. Its relatives, the astrapotheres, vaguely resembled tapirs.

The mandibular symphysis was quite long and flat on the interior surface. it had two pairs of small incisors, framed posteriorly and a bit laterally by a pair of very strong, long-rooted, very curved and forward-protruding teeth. Behind them was a large diastema, followed by another pair of very strong teeth, slightly curved forward but with a short root. These two teeth were approximately located near the middle of the symphysis. Like Trigonostylops , the symphysis of Shecenia had a flat lower edge.

Classification

Shecenia was first described in 1935 by George Gaylord Simpson, based on fossils found in probably Lower Eocene terrains from Argentina. The type species is Shecenia ctirneru, but other remains from the Late Paleocene have also been attributed to the genus.

Shecenia is considered an archaic astrapothere, a mysterious group of South American mammals, vaguely reminding of tapirs. Shecenia is considered to be a member of Trigonostylopidae, a clade comprising some of the oldest and more archaic members of Astrapotheria.

Bibliography

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