Biology Bulletin

, Volume 39, Issue 7, pp 618–626 | Cite as

Dentition in Pacific walrus (Odobenus rosmarus divergens) calves of the year

  • N. V. Kryukova


The oral cavity and teeth were examined in Pacific walrus calves of the year that died or were harvested on Cape Vancarem and Koluchin Island, the Chukchi Sea, in September to October 2010. The order of gingival eruption of teeth, the resultant dental formula in calves of the year and 1.5-year-old animals, and the dental formula after alveolar eruption of teeth were determined. The number of teeth after gingival eruption in calves of the year did not depend on their body length and sex. The loss of some teeth, mainly incisors, was recorded in individuals aged 5–6 months. Already at early developmental stages, functional teeth were found to differ significantly from other (rudimentary) teeth in their weight, total size, and the size of apical foramen. Some individuals had milk teeth, which were either gingivally erupted or partly remained within soft tissues. Cases of aberration in dentition that require additional studies were recorded.


pinnipeds Pacific walrus teeth dental formula calf of the year 


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Copyright information

© Pleiades Publishing, Ltd. 2012

Authors and Affiliations

  1. 1.All-Russia Research Institute of Fisheries and Oceanography (VNIRO)MoscowRussia

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