DENTAL ANOMALY IN  HAPALODECTES DUX  (HAPALODECTIDAE, MESONYCHIA) FROM THE LATE PALEOCENE OF MONGOLIA

A. V. Lopatin; Лопатин А. В.

doi:10.31857/S2686738923700361

DENTAL ANOMALY IN HAPALODECTES DUX (HAPALODECTIDAE, MESONYCHIA) FROM THE LATE PALEOCENE OF MONGOLIA

Authors: Lopatin A.V.¹
Affiliations:
1. Borissiak Paleontological Institute, Russian Academy of Sciences
Issue: Vol 512, No 1 (2023)
Pages: 474-479
Section: Articles
URL: https://vestnik.nvsu.ru/2686-7389/article/view/651076
DOI: https://doi.org/10.31857/S2686738923700361
EDN: https://elibrary.ru/SRNBWU
ID: 651076

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Abstract

The holotype of Hapalodectes dux Lopatin, 2001 from the Upper Paleocene of Mongolia (Tsagan-Khushu locality, Naran Bulak Formation, Zhigden Member) is a lower jaw with complete dentition, showing healed alveoli in place of the right P₃. Examination of the holotype using X-ray microtomography revealed a rare dental anomaly previously unknown in fossil mammals, namely the presence of the inverted (positioned upside down and rotated lingual side labially) impacted premolar inside the dentary. The cause of this anomaly may be an aberration of a tooth bud location or an injury.

Keywords

Hapalodectes, Mesonychia, Paleocene, Mongolia, mandible, computed tomography, failure of tooth eruption, impaction, inversion, ectopy, heterotopy

About the authors

A. V. Lopatin

Borissiak Paleontological Institute, Russian Academy of Sciences

Author for correspondence.
Email: alopat@paleo.ru
Russian Federation, Moscow

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