Ginkgo-toothed Beaked Whale - Mesoplodon ginkgodens | |||||||||||||||||||||||||||||||
Taxonomy & Nomenclature
Physical Description / Field IdentificationAdult male ginkgo-toothed beaked whales are dark gray, with light spots; females are apparently lighter. Unlike most other beaked whales, they generally do not appear to be scarred. The throat grooves, dorsal fin, and tail flukes are typical for Mesoplodon species. Bulls have flattened tusks that barely break the gumline, slightly behind the middle of the lower jaw; erupted teeth are absent in females. Maximum known sizes are 4.9 m (females) and 4.8 m (males). At birth, they are thought to be about 2-2.5 m. Can be Confused WithThe uniform dark pigmentation, small posteriorly-placed teeth, and lack of characteristic ziphiid scars may allow a tentative classification of adult male ginkgo-toothed beaked whales. Otherwise, this species will be virtually indistinguishable from other mesoplodonts. DistributionThis species is known from widely scattered sightings, strandings, and collections (albeit sparse) in temperate and tropical waters of the Indo-Pacific Ocean. Ecology and BehaviorAlmost nothing is known of the biology of the ginkgo-toothed beaked whale. Feeding and PreyGinkgo-toothed beaked whales are presumed to be primarily squid eaters. Threats and StatusThis species has occasionally been taken by Japanese whalers. Currently, ginkgo-toothed beaked whales are ‘Data Deficient’ (IUCN) and ‘Not Listed’ (ESA). LinksN/A
ReferencesDalebout, M.L. 2002. Species identity, genetic diversity, and molecular systematic relationships among the Ziphiidae (beaked whales). Ph.D. dissertation, University of Auckland, New Zealand. Mead, J.G. 1989. Beaked whales of the genus Mesoplodon. pp. 349-430 in S.H. Ridgway and R. Harrison, eds. Handbook of marine mammals, Vol. 4: River dolphins and the larger toothed whales. Academic Press. Pitman, R.L. 2002. Mesoplodont whales Mesoplodon spp. pp. 738-742 in W.F. Perrin, B. Würsig and J.G.M. Thewissen, eds. Encyclopedia of marine mammals. Academic Press. |
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