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://journals.rcsi.science/2686-7389/article/view/140860
DOI: https://doi.org/10.31857/S2686738923700361
EDN: https://elibrary.ru/SRNBWU
ID: 140860

Cite item

Full Text

Open Access
Restricted Access

Access granted
Restricted Access

Subscription Access

Abstract
About the authors
References
Supplementary files
Statistics

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

References

Лопатин А.В. Древнейший Hapalodectes (Mesonychia, Mammalia) из палеоцена Монголии // Палеонтологический журнал. 2001. № 4. С. 90–96.
Бадамгарав Д., Решетов В.Ю. Палеонтология и стратиграфия палеогена Заалтайской Гоби. М.: Наука, 1985 (Тр. ССМПЭ. Вып. 25).
Lopatin A.V. Early Paleogene insectivore mammals of Asia and establishment of the major groups of Insecti-vora // Paleontological Journal. 2006. V. 40. Suppl. 3. P. S205–S405.
Beard K.C., Wang Y.-Q., Meng J. et al. Paleocene Hapalodectes (Mammalia: Mesonychia) from Subeng, Nei Mongol: further evidence of “East of Eden” dispersal at the Paleocene-Eocene boundary // Vertebrata PalAsiatica. 2010. V. 48. № 4. P. 375–389.
Solé F., De Bast E., Yang J. et al. The first species of Hapalodectes (Mesonychia, Mammalia) from the middle Paleocene of China (Qianshan Basin, Anhui Province) sheds light on the initial radiation of hapalodectids // Palaeontology. 2017. V. 60. № 3. P. 433–449.
Charlier C. Intraoral radiographs: identifying common pathology // Today’s Veterinary Practice. 2022 (July–August). P. 86–96.
Miles A.E.W., Grigson C. Colyer’s variations and diseases of the teeth of animals. Cambridge: Cambridge University Press, 1990.
Wilson R.W. Two cases of dental anomaly in Early Tertiary mammals // Transactions of the Kansas Academy of Science. 1955. V. 58. № 4. P. 514–518.
Rose K.D., Smith B.H. Dental anomaly in the Early Eocene condylarth Ectocion // Journal of Paleontology. 1979. V. 53. № 3. P. 756–760.
Lucas S.G., Schoch R.M. Paleopathology of Early Cenozoic Coryphodon (Mammalia; Pantodonta) // Journal of Vertebrate Paleontology. 1987. V. 7. № 2. P. 145–154.
Libed S.A., Lucas S.G. Paleopathology of a Paleocene periptychid (Mammalia; Condylarthra) jaw from the San Juan Basin, New Mexico // New Mexico Museum of Natural History and Science Bulletin. 2000. № 16. P. 151–153.
Лопатин А.В. Аномалии зубной системы у Nesophontidae (Lipotyphla, Mammalia) из плейстоцена Кубы // Доклады Российской академии наук. Науки о жизни. 2021. Т. 497. С. 125–130.
Colyer F. Variations of the teeth of the green monkey in St. Kitts // Proceedings of the Royal Sociey of Medicine. 1948. V. 41. P. 845–848.
Fine M.D. An abnormal P2 in Canis cf. C. latrans from the Hagerman fauna of Idaho // Journal of Mammalogy. 1964. V. 45. № 3. P. 483–485.
Vilà C., Urios V., Castroviejo J. Tooth losses and anomalies in the wolf (Canis lupus) // Canadian Journal of Zoology. 1993. V. 71. P. 968–971.
Powers P.M., Mead A.J. Dental and mandibular anomalies in white-tailed deer (Odocoileus virginianus) from central Georgia // Georgia Journal of Science. 2019. V. 77. № 2. Art. 15. P. 1–11.
Jentzsch M., Kraft R., Lemkul A. et al. Anomalies and pathological changes of skulls and dentition of wild small mammal species from Germany // Journal of Vertebrate Biology. 2020. V. 69. № 4. P. 1–19.
Jacobs R., Willems G. Inverted eruption of a supplemental lower premolar: report of an unusual case // International Journal of Paediatric Dentistry. 2003. V. 13. № 1. P. 46–50.
Ulusoy A.T., Akkocaoglu M., Akan S. et al. Reimplantation of an inverted maxillary premolar: case report of a multidisciplinary treatment approach // Journal of Clinical Pediatric Dentistry. 2009. V. 33. № 4. P. 279–282.
Mohan S., Kankariya H., Fauzdar S. Impacted inverted teeth with their possible treatment protocols // Journal of Maxillofacial and Oral Surgery. 2012. V. 11. № 4. P. 455–457.